Active filters amplify desired signals while rejecting unwanted frequencies, and can be tailored to meet application-specific requirements in electronics.
Amplifiers boost signal strength, match impedance levels, and are essential in many circuit systems, including audio, broadcasting, and telecommunications.
Batteries store and provide electrical energy, come in various types and sizes for multiple uses, rechargeable or single-use.
Capacitors store electrical charge with metallic plates and a dielectric; types vary and can be combined for specific circuit characteristics.
Chip carriers and sockets provide an interface between components and PCBs, enabling easy replacement or upgrading without soldering.
Circuit protection devices prevent damage from overcurrent flow, including fuses, breakers, surge protectors, and voltage regulators.
Connector accessories and support devices aid connector function and longevity, including backshells, grips, clamps, and ties; must be compatible with connector type.
Connectors join electronic circuits to transfer signals and power, come in various sizes and shapes, and include support accessories.
Converters transform DC input to another voltage level, essential in electronic systems, renewable energy, and automotive electronics.
Crystals and resonators generate and stabilize frequency signals via piezoelectricity. They are used in timing, frequency control, and filters. Crystals are quartz and resonators are ceramic with a built-in capacitor.
Semiconductor diodes control current flow in one direction (uni-directionality) via low resistance. Useful for rectification, voltage regulation, detection, and digital logic.
Discover essential electronic components for your devices, including CPU accelerators, system cache controllers, computer processors, motherboards, and graphics computing systems. Enhance device performance and connectivity with reliable components engineered for seamless integration and optimal functionality.
Fiber optics use light pulses to transmit data over long distances. They have superior bandwidth capacity, low signal attenuation, and secure physical properties. They are essential in telecommunications networks today.
Filters enhance signal processing by selectively passing desired frequencies while suppressing unwanted ones. Filters can be passive (using capacitors, resistors, and inductors) or active (using transistors or amplifiers).
Flash devices are non-volatile storage solutions that offer fast read and write speeds, making them ideal for applications requiring high-speed data transfer. These devices utilize flash memory technology, providing reliable storage for data-intensive tasks such as gaming, multimedia, and enterprise-level applications.
General purpose ICs consist of multiple individual circuits or components (e.g., logic gates, amplifiers, oscillators, etc.) that are combined onto a single integrated circuit chip for a smaller physical footprint.
I/O and storage controllers are crucial components in computer systems, managing input/output operations and storage devices. These controllers facilitate efficient data transfer between peripherals, storage drives, and the central processing unit (CPU), enhancing system performance and enabling seamless connectivity.
Inductors store energy in magnetic fields, oppose sudden changes in current flow and prevent electrical surges. Common inductor applications include power supplies, signal filters, and oscillators.
Interface ICs allow efficient device connectivity with high-speed data transfer and low power consumption.They can be ASIC or FPGA types, and may perform additional functions such as sensing, storage, and conversion.
Logic ICs can be used for storage, memory, amplification, and multiplexing. They perform fundamental logical operations on digital input signals (1, 0, H, L) to generate a corresponding digital output signal.
Memory modules are essential components in electronic devices, storing data temporarily or permanently for processing and retrieval. From volatile RAM (Random Access Memory) to non-volatile ROM (Read-Only Memory), memory technologies vary in speed, capacity, and functionality, catering to diverse application requirements.
Memory ICs store digital data and retain the information even when the power is turned off. They come in various types, like RAM (Random Access Memory) for fast data access, and ROM (Read-Only Memory) for permanent data storage.
Miscellaneous semiconductor components are a diverse category of electronic components that combines elements from a mix of component devices.
Optoelectronic devices interact with light. This family of devices can emit light, detect light, generate current, and transmit light signals for long-distance communication.
Oscillators generate repetitive waveforms, such as sine, square, or triangle waves. They are commonly used to produce stable and precise frequencies for applications like clocks, signal generation, and communication systems.
Other Function Semiconductor components are a diverse category of semiconductor components that perform a range of specialized functions.
Passive component networks operate without a power source and support data transmission within system by performing filtering, energy storage, and/or signal coupling functions.
Peripheral ICs (Integrated Circuits) are designed to control and manage the peripheral devices connected to a computer or other electronic device.
Programmable Logic ICs are user-programmable devices that allow designers to create custom logic circuits. These cost saving ICs offer real-time data processing and maximum design flexibilty.
RF (Radio Frequency) and microwave devices are used in telecommunications, wireless communications, and electronic systems. These devices include amplifiers, attenuators, filters, mixers, oscillators, and antennas, and a host of other components.
Voltage regulators are used to ensure a constant output voltage despite power fluctuations and load changes. Linear and switching regulators are common types used to maintain voltage stability.
Relays are electromagnetic switches that are used to control the flow of electrical current in an electrical circuit. Relays are a safe means of providing isolation between a controlling circuit and a controlled circuit.
Resistors control the flow of electrical current in a circuit by introducing a set resistance. These passive components reduce current flow, adjust signal levels, and bias active elements in circuits.
Transducers convert energy from one form to another and are crucial in sensing, audio and control systems. They transform physical measures like temperature, pressure, or sound into electrical signals for circuits.
Storage drives are hardware devices used to store and retrieve digital data in computers and electronic devices. These drives come in various forms, including hard disk drives (HDDs), solid-state drives (SSDs), and hybrid drives, offering different levels of capacity, speed, and durability to suit specific storage needs.
Storage media encompass physical or digital mediums used for storing and preserving digital data. From optical discs and magnetic tapes to USB flash drives and memory cards, storage media come in diverse formats and capacities, offering flexibility and reliability for data storage and archival purposes.
Storage systems comprise hardware and software components designed to manage and store digital data efficiently. These systems range from simple standalone devices to complex network-attached storage (NAS) and storage area network (SAN) solutions, providing scalable storage capacity and data protection features for businesses and enterprises.
Switches control electrical current flow by making or breaking connections. These devices vary in design and application, from basic on/off switches to complex industrial automation systems.
Telecom integrated circuits (ICs) are specialized electronics for telecommunications, tailored to high data rates, low power use, and reliable long-distance transmission. These devices include amplifiers, filters, ADCs, DACs, and more-- and they are often integrated on one chip for specific telecom tasks.
Terminal blocks, or connection terminals, are modular blocks that bring together multiple electrical wires at one connection point. They offer a reliable, organized way to terminate cables.
Thermal management devices control heat in electronic systems, preventing overheating and ensuring optimal performance and reliability. Examples include heat sinks, fans, and thermal interface materials that dissipate or transfer heat away from components.
Transformers are devices that alter electrical voltage levels between circuits through electromagnetic induction. They are vital in power distribution, converting high-voltage electricity for transmission and lower voltage for safe usage.
Transistors are 3-layer semiconductor devices that regulate the flow of electrical current. They function as amplifiers, boosting weak signals, and as switches, controlling the flow of current between terminals.
Triggering devices initiate electronic processes or events in response to specific conditions. These devices support many automated tasks such as activating switches and signals, or turning on lights when motion is detected.
Video cards, also known as graphics cards or GPU (Graphics Processing Unit), are essential components in computers, responsible for rendering graphics and images on display devices. These cards feature dedicated processors and memory, delivering smooth and immersive visual experiences for gaming, multimedia, and professional applications.
Choose from over than a million of proven quality materials. Over 300 manufacturers are presented. From renowned major international players to small independent companies with a proven track record in local markets.
Featured manufacturers
The Apem Components 4731/8A02UU is a black pushbutton switch with silver terminals, offering an electrical life of 10k cycles. With SPST switch function and Melamine-Phenolic insulator material, it is ideal for applications requiring ON-OFF contact function at temperatures ranging from -20 to 65°C.
Median Price
-
Lifecycle Status
Suppliers In-Stock
3
In-Stock Inventory
1k+
Vyrian
1+ parts
100+ parts
1k+ parts
10k+ parts
Nova Conductors
VNN
AZTECH Wire
$19.082
Continental Prestige Electronics
Argo Parts USA
Bastille Electronics
The black color provides a sleek and professional look to the pushbutton switch, making it suitable for a variety of applications.
Silver terminals offer excellent conductivity and durability, ensuring a reliable connection in the switch.
With a high electrical life of 10000 cycles, this pushbutton switch is long-lasting and can endure frequent use without compromising performance.
The high insulation resistance value ensures minimal leakage of current, enhancing the safety and efficiency of the switch.
The compact body width of 12 inches allows for easy installation and integration into various equipment or control panels.
The length of the bushing provides secure mounting and stability for the pushbutton switch.
The single-pole single-throw switch function offers a simple ON-OFF operation, making it user-friendly and straightforward to use.
The melamine-phenolic insulator material provides excellent resistance to heat and electrical insulation properties for safe operation of the switch.
The compact body height of 14mm allows for space-saving installation in various devices or control panels.
With a maximum operating temperature of 65°C, this pushbutton switch can withstand high temperatures and harsh environments.
The maximum AC contact current of 6A allows for handling moderate electrical loads to control various devices or equipment effectively.
With a minimum operating temperature of -20°C, this pushbutton switch is suitable for use in cold environments without compromising functionality.
Silver terminal finish ensures excellent conductivity and corrosion resistance, maintaining a reliable connection in the switch.
The actuator travel distance of 4.5mm provides tactile feedback and precise operation when pressing the pushbutton switch.
Silver end contact material ensures reliable electrical contact and longevity in the switch for consistent performance.
The button plunger actuator type offers a comfortable and ergonomic design for easy and convenient operation of the pushbutton switch.
As a pushbutton switch, it provides a simple and intuitive interface for users to control various functions or devices with a push of a button.
The maximum AC rating of 6A at 125VAC allows for reliable performance in handling electrical loads and controlling devices effectively.
The dielectric withstand voltage of 2000VRMS ensures insulation and safety in the switch, preventing electrical breakdown under high voltage conditions.
With an ON-OFF contact function, this pushbutton switch offers a straightforward control option for users to turn devices or functions on and off easily.
The pushbutton switch is packed in a box, providing protection during storage and transportation, ensuring the product arrives in optimal condition.
The body length/diameter of 19mm offers a compact and space-saving design for easy installation in various equipment or control panels.
Silver center contact material ensures reliable electrical connection and longevity in the switch for consistent performance.
The length of the actuator provides comfortable and ergonomic operation when pressing the pushbutton switch for user convenience.
With a latched switch action, the pushbutton switch stays in the position (ON or OFF) until manually reset, providing a stable and secure control option.
The quick connect termination type allows for easy and fast installation of the switch, reducing assembly time and effort.
The low contact resistance of 10 mohm ensures minimal energy loss and heat generation in the switch for efficient and reliable performance.
The diameter of the bushing provides a secure and stable mounting option for the pushbutton switch, ensuring durability and longevity in operation.
The maximum AC contact voltage of 125V allows for reliable performance in handling electrical loads and controlling devices effectively.
The threaded panel mounting feature offers secure installation in control panels or equipment, providing stability and durability for long-term use.
The terminal length of 0.322 inches provides a secure connection and easy installation of wires to the pushbutton switch for reliable operation.
The polyamide actuator material offers durability and resistance to impact or wear, ensuring long-lasting performance of the pushbutton switch.
Pushbutton Switches 4731/8A02UU attributes and parameters. Explore more Pushbutton Switches devices from Apem Components
Color (Actuator):
Length (Actuator):
Material (Actuator):
Actuator Travel (mm):
Type (Actuator):
Additional Features:
Body Width:
Body Height:
Body Length/Diameter:
Diameter (Bushing):
Length (Bushing):
Center Contact Material:
AC Maximum Rating R Load (Contact):
Maximum AC Contact Current:
Contact Function:
Contact Resistance:
Maximum AC Contact Voltage:
Dielectric Withstand Volts (V):
Electrical Life:
End Contact Material:
Insulation Resistance:
Insulator Material:
JESD-609 Code:
Mounting Feature:
Maximum Operating Temperature:
Minimum Operating Temperature:
Packing Method:
Switch Action:
Switch Function:
Switch Type:
Terminal Finish:
Terminal Length:
Terminal Material:
Termination Type:
4731/8A02UU Switches trade compliance attributes, and parameters.
ECCN
EAR99
ECCN Governance
EAR
HTS
8536.50.70.00
SB
HMI is a quickly changing sector in which APEM continues to strengthen its leadership. Since 1952, APEM has been developing and marketing an extensive portfolio of human-machine interfaces. Today, we are able to produce more than 50,000 distinct part numbers. Our offer is continuously evolving to always respect the applicable standards and anticipate the challenges of our customers and the markets in which they operate. If APEM's activity was initially focused on switches, it has diversified over the years. Switches and buttons of all types, LED indicators, joysticks of all sizes, keyboards and integrated solutions, our group has integrated many different types of know-how and is now able to offer its expertise to thousands of customers around the world. We control all phases, from product development to manufacturing, thanks to our vertical integration of production and our mastery of advanced technologies. This enables us to respond effectively to the most complex specifications. We not only have the necessary know-how, but also the right equipment and personnel. We recruit and train our teams to always offer the best product-service combination to each of our customers.
2N2222A
Gec Plessey Semiconductors
NPN; Configuration: SINGLE; Surface Mount: NO; Nominal Transition Frequency (fT): 300 MHz; Maximum Power Dissipation (Abs): .5 W; Maximum Collector Current (IC): .8 A;
Rectron
NPN; Configuration: SINGLE; Surface Mount: NO; Nominal Transition Frequency (fT): 300 MHz; Maximum Collector Current (IC): .8 A; Package Shape: ROUND;
1N4148
Cheng-yi Electronic
RECTIFIER DIODE; Terminal Position: AXIAL; Terminal Form: WIRE; No. of Terminals: 2; Surface Mount: NO; Package Shape: ROUND;
SS14
General Instrument
RECTIFIER DIODE; Terminal Position: DUAL; Terminal Form: C BEND; No. of Terminals: 2; Surface Mount: YES; Package Shape: RECTANGULAR;
LM358N
Freescale Semiconductor
OPERATIONAL AMPLIFIER; Temperature Grade: COMMERCIAL; Terminal Form: GULL WING; No. of Terminals: 8; Package Code: DIP; Package Shape: RECTANGULAR;
Samsung
OPERATIONAL AMPLIFIER; Temperature Grade: COMMERCIAL; Terminal Form: THROUGH-HOLE; No. of Terminals: 8; Package Code: DIP; Package Shape: RECTANGULAR;
LL4148
Silicon Standard
RECTIFIER DIODE; Terminal Position: END; Terminal Form: WRAP AROUND; No. of Terminals: 2; Surface Mount: YES; Package Shape: ROUND;
IRLML6402TRPBF
Infineon Technologies
IRLML6402TRPBF by Infineon is a P-CHANNEL FET for SWITCHING applications. It features a 20V DS Breakdown Voltage, 22A IDM, and 0.065 ohm RDS(on). With a small outline package and matte tin finish, it operates in temperatures from -55 to 150 °C.
BAV99
Panasonic
MIXER DIODE; Terminal Position: DUAL; Terminal Form: GULL WING; No. of Terminals: 3; Surface Mount: YES; Package Shape: RECTANGULAR;
2N7002
Calogic
N-CHANNEL; Configuration: SINGLE WITH BUILT-IN DIODE; Surface Mount: YES; Maximum Power Dissipation (Abs): .2 W; Peak Reflow Temperature (C): NOT SPECIFIED; Terminal Position: DUAL;
LM7805CT
Onsemi
FIXED POSITIVE SINGLE OUTPUT STANDARD REGULATOR; No. of Terminals: 3; Package Code: TO-220; Terminal Form: THROUGH-HOLE; Maximum Input Voltage Absolute: 35 V; Maximum Voltage Tolerance: 5 %;
STMicroelectronics
N-CHANNEL; Configuration: SINGLE WITH BUILT-IN DIODE; Surface Mount: YES; Maximum Power Dissipation (Abs): .35 W; Maximum Drain Current (ID): .2 A; Transistor Application: SWITCHING;
FDN5618P
Fairchild Semiconductor
P-CHANNEL; Configuration: SINGLE WITH BUILT-IN DIODE; Surface Mount: YES; Maximum Power Dissipation (Abs): .5 W; Transistor Element Material: SILICON; Moisture Sensitivity Level (MSL): 1;
OPA2277UA/2K5E4
Texas Instruments
OPA2277UA/2K5E4 by Texas Instruments is a dual operational amplifier with low-offset and micropower features. It has a max input offset voltage of 100uV, nominal common mode reject ratio of 140dB, and min slew rate of 0.8V/us. Ideal for industrial applications requiring precise signal amplification in compact designs.
AT90CAN128-16AUR
Microchip Technology
AT90CAN128-16AUR by Microchip: 16 MHz clock, 8-bit data RAM, and 131072 ROM words. Ideal for industrial applications with CAN, SPI, TWI connectivity and low power mode. Contains 4 timers, 8 ADC channels, and supports up to 10-bit analog to digital conversion.
Transys Electronics
2N2222A by Texas Instruments is a small signal NPN bipolar junction transistor (BJT) with a max collector-emitter voltage of 40V and a max collector current of 0.8A. It is commonly used for switching applications due to its fast turn on/off times (35ns/285ns) and high transition frequency (300MHz).
Pro-an Electronic
FT232RQ-REEL
FTDI
FTDI's FT232RQ-REEL is a USB bus controller with 32 terminals, operating at 3.3-5.25V. It supports data transfer rates up to 60MBps and clock frequency of 12.02MHz, suitable for RS232/RS422/RS485 interfaces in various applications like industrial automation and communication systems.
International Rectifier
P-CHANNEL; Configuration: SINGLE WITH BUILT-IN DIODE; Surface Mount: YES; Maximum Power Dissipation (Abs): 1.3 W; Peak Reflow Temperature (C): 260; Package Style (Meter): SMALL OUTLINE;
51-151.022
Eao
PUSHBUTTON SWITCH;
1-1825027-8
Tyco Electronics Amp
PUSHBUTTON SWITCH; Mounting Feature: THROUGH HOLE-RIGHT ANGLE; Switch Function: SPST; Type (Actuator): BUTTON TYPE; Body Width: 6.62 inch; Switch Action: MOMENTARY;
CW4L-M1E11Q4R
Idec
CW4L-M1E11Q4R by Idec is a DPST pushbutton switch with red LED illumination. It has an electrical life of 2M cycles, insulation resistance of 100M ohm, and sealing ratings of IP65, IP66, and IP67. Ideal for applications requiring a reliable illuminated pushbutton switch with high durability and waterproof capabilities.
1571625-1
TE Connectivity
TE Connectivity's 1571625-1 is a black pushbutton switch with SPST function. Made of polyethylene, it has a body width of 6.2mm and height of 2mm. Ideal for panel mounting applications, it operates b/w -35 to 85°C with max current rating of 0.05A at 24VDC.
P9-213221
Otto Engineering
Otto Engineering's P9-213221 pushbutton switch features DPDT switch function, IP64 sealing, and 25000 cycle electrical life. Ideal for applications requiring a momentary-tactile switch with 5A@115VAC AC max rating and 5A@28VDC DC max rating.
1241.6634.1184000
Schurter Ag
IPC3SAD2L0G
Apem Components
A01ES-DM+A0154B-D
A01ES-DM+A0154B-D by Apem Components is a red DPST pushbutton switch with IP40/IP65 sealing. It has an electrical life of 6050 cycles, insulation resistance of 50MΩ, and operates b/w -20°C to 55°C. Ideal for panel mounting applications requiring a latched switch action with a max AC contact current of 6A@250VAC.
IPR3SAD7/1L0G
A3CT-90A1-24EW
Omron
1825098-2
Tyco Electronics Alcoswitch
PUSHBUTTON SWITCH; Mounting Feature: THROUGH HOLE-RIGHT ANGLE; Switch Function: SPST; Type (Actuator): EXTENDED TYPE; Maximum Operating Temperature: 65 Cel; Maximum DC Contact Current: .02 A;
ABW401R
AML21CBA2AD
Honeywell Sensing And Control
AML21CBA2AD by Honeywell is a DPDT pushbutton switch with 25000 cycles electrical life. It has a max DC contact voltage of 24V and can handle up to 2A@24VDC load. Ideal for panel mounting applications requiring latched switch action.
TPF11CGPC004
TE Connectivity's TPF11CGPC004 is a black pushbutton switch with polyester housing and epoxy terminal sealing. It features SPST switch function, 0.4A AC contact current, 20V DC contact voltage, and gold over nickel center contact plating. Ideal for panel mounting applications requiring a max operating force of 3.92N.
A22L-GA-T1-01M
Omron A22L-GA-T1-01M is a durable pushbutton switch with 500000 cycles electrical life, IP65 sealing, and SPST switch function. Ideal for panel mounting applications in industrial settings with operating temperatures ranging from -20°C to 55°C.
9001SKR9P35
Schneider Electric Sa
9023-09
Littelfuse
PUSHBUTTON SWITCH; Manufacturer Series: 9023-09;
IPR1SAD2
IPR1SAD2 by Apem Components is a black pushbutton switch with an electrical life of 200,000 cycles and insulation resistance of 1,000,000,000 ohms. It is commonly used in applications requiring a latched switch function and a max DC contact current of 4A at 12VDC.
1241.2856.016
Schurter Ag's 1241.2856.016 is a SPST pushbutton switch with ZINC DIE CAST housing, LED illumination, and SILVER plated contacts. With an electrical life of 1000000 cycles, it is suitable for applications requiring momentary switch action in environments with temperatures ranging from -20 to 60 °C.
XB4BA42
XB4BA42 by Schneider Electric Sa is a flush type pushbutton switch with SPST switch function. It features a red LED illumination, IK03; IP66 sealing, and 1000000 cycle electrical life. Ideal for panel mounting applications, it has a max operating temperature of 70°C and can handle up to 6A@120VAC AC max rating R load.
Partstack™ will investigate all reported instances of potential suspect/counterfeit part listings.
4731/8A02
PUSHBUTTON SWITCH; Mounting Feature: PANEL MOUNT-THREADED; Switch Function: SPST; Type (Actuator): BUTTON PLUNGER; Contact Function: ON-OFF; Body Length/Diameter: 19 mm;
4731/8A01UU
PUSHBUTTON SWITCH; Mounting Feature: PANEL MOUNT-THREADED; Switch Function: SPST; Type (Actuator): BUTTON PLUNGER; Contact Function: ON-OFF; Maximum AC Contact Current: 6 A;
4731/8A03UU
PUSHBUTTON SWITCH; Mounting Feature: PANEL MOUNT-THREADED; Switch Function: SPST; Type (Actuator): BUTTON PLUNGER; Contact Function: ON-OFF; Termination Type: QUICK CONNECT;
4731/8A05UU
PUSHBUTTON SWITCH; Mounting Feature: PANEL MOUNT-THREADED; Switch Function: SPST; Type (Actuator): BUTTON PLUNGER; Contact Function: ON-OFF; Maximum Operating Temperature: 65 Cel;
4731/8A06UU
PUSHBUTTON SWITCH; Mounting Feature: PANEL MOUNT-THREADED; Switch Function: SPST; Type (Actuator): BUTTON PLUNGER; Contact Function: ON-OFF; Dielectric Withstand Volts (V): 2000VRMS;
4731/8A07/1UU
4731/8A09UU
PUSHBUTTON SWITCH; Mounting Feature: PANEL MOUNT-THREADED; Switch Function: SPST; Type (Actuator): BUTTON PLUNGER; Contact Function: ON-OFF; End Contact Material: SILVER;
4731C06UU
PUSHBUTTON SWITCH; Mounting Feature: PANEL MOUNT-THREADED; Switch Function: SPST; Type (Actuator): BUTTON PLUNGER; Contact Function: ON-OFF; Solderability: HAND;
4731C02UU
4731/8A06
PUSHBUTTON SWITCH; Mounting Feature: PANEL MOUNT-THREADED; Switch Function: SPST; Type (Actuator): BUTTON PLUNGER; Contact Function: ON-OFF; Diameter (Bushing): .472 inch;
4731/8A07/1
4731A07/1
4731A09
4731/8A05
PUSHBUTTON SWITCH; Mounting Feature: PANEL MOUNT-THREADED; Switch Function: SPST; Type (Actuator): BUTTON PLUNGER; Contact Function: ON-OFF; Insulation Resistance: 1000000000 ohm;
4731A02
4731/8A09
PUSHBUTTON SWITCH; Mounting Feature: PANEL MOUNT-THREADED; Switch Function: SPST; Type (Actuator): BUTTON PLUNGER; Contact Function: ON-OFF; Length (Bushing): .492 inch;
4731A01
4731/8A01
PUSHBUTTON SWITCH; Mounting Feature: PANEL MOUNT-THREADED; Switch Function: SPST; Type (Actuator): BUTTON PLUNGER; Contact Function: ON-OFF; Terminal Length: .322 inch;
4731/8A03
4731C05
Supply Digital Components
$106.00
$54.25
$11.90
$7.29
Quantity
12,000 In-Stock
Total price ≈ $80,197.29
© 2023 All rights reserved