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
MK23-80-C-2 by Standex-Meder Electronics is a magnetic proximity sensor with a response time of 100 us. It operates in temperatures ranging from -40 to 130 °C and features a cylindrical package shape. Ideal for surface mount applications, this sensor has a body length/diameter of 7 mm and solder termination.
Median Price
$2.270
Lifecycle Status
Suppliers In-Stock
9
In-Stock Inventory
1k+
Arrow
1+ parts
$0.067
100+ parts
$0.064
1k+ parts
-
10k+ parts
DigiKey
$1.578
$1.316
Mouser Electronics
$1.580
$1.320
$1.160
Master Electronics
$1.230
$1.120
Verical
$3.397
$1.243
Nova Conductors
$1.273
Electro Sonic
$1.650
$1.110
IBS Electronics
$1.725
$1.571
Vyrian
Continental Prestige Electronics
$1.247
Argo Parts USA
Aztec Data Supply Inc.
$2.053
Perfect Parts
This allows for accurate detection of magnetic objects, making it suitable for various industrial applications.
The cylindrical shape makes it easy to install in tight spaces or on equipment without taking up too much room.
With a high maximum operating temperature, this sensor can be used in a wide range of environments without overheating.
The quick response time ensures timely detection and action, making it ideal for high-speed processes.
The low minimum operating temperature allows this sensor to be used in cold environments without any issues.
The compact size of the sensor makes it versatile and easy to integrate into different systems.
The solder termination makes it easy to connect the sensor to other components securely.
The surface mount feature simplifies installation and allows for flexibility in placement on machinery or equipment.
Proximity Sensors MK23-80-C-2 attributes and parameters. Explore more Proximity Sensors devices from Standex-Meder Electronics
Body Length/Diameter:
Mounting Feature:
Maximum Operating Temperature:
Minimum Operating Temperature:
Package Shape or Style:
Response Time:
Sensors or Transducers Type:
Termination Type:
2N7002-T1-E3
Vishay Intertechnology
Vishay Intertechnology's 2N7002-T1-E3 is a N-CHANNEL FET for SWITCHING applications. Features include 60V DS Breakdown Voltage, 0.115A Drain Current, and 7.5 ohm On Resistance. With ENHANCEMENT MODE operation, this GULL WING transistor is ideal for small outline surface mount designs up to 150°C.
RN41N-I/RM
Microchip Technology
Microchip Technology's RN41N-I/RM is a telecom IC with 35 terminals, operating from -40 to 85°C. It has a supply voltage of 3.3V and is surface mountable in industrial applications. The package style is rectangular, measuring 13.2mm x 20.1mm with a seated height of 2.2mm, suitable for telecom interface functions.
M39029/56-351
Itt Cannon
CONNECTOR ACCESSORY; MIL Conformity: YES; Terminal Type: WIRE; IEC Conformity: NO; Alternate Contact Sources: ITT CANNON; Associated Military - Specifications: MIL-C-38999;
LM317TG
Texas Instruments
LM317TG by Texas Instruments is an adjustable positive single output standard regulator with a max output voltage of 37V and max output current of 1.5A. It operates in temperatures ranging from 0 to 125°C, making it suitable for various applications requiring precise voltage regulation in electronic circuits. The package style is flange mount, with a rectangular shape and through-hole terminals for easy installation.
261
Deltrol Controls
Other Relays;
LL4148
Good-ark Electronics
RECTIFIER DIODE; Terminal Position: END; Terminal Form: WRAP AROUND; No. of Terminals: 2; Surface Mount: YES; Package Shape: ROUND;
SMBJ18CA
Db Lectro
TRANS VOLTAGE SUPPRESSOR DIODE; Terminal Position: DUAL; Terminal Form: C BEND; No. of Terminals: 2; Surface Mount: YES; Package Shape: RECTANGULAR;
USB3320C-EZK-TR
Microchip Technology's USB3320C-EZK-TR is a Bus Controller IC with 32 terminals, operating at 1.6-2V. It supports USB bus compatibility, clock frequency up to 60MHz, and CMOS technology. Ideal for applications requiring Universal Serial Bus peripherals in compact designs with low power consumption.
LM317AEMP/NOPB
National Semiconductor
ADJUSTABLE POSITIVE SINGLE OUTPUT STANDARD REGULATOR; No. of Terminals: 3; Package Code: SOP; Terminal Form: GULL WING; Qualification Status: Not Qualified; Width: 3.56 mm;
1N4148
Grande Electronics
RECTIFIER DIODE; Terminal Position: AXIAL; Terminal Form: WIRE; No. of Terminals: 2; Surface Mount: NO; Package Shape: ROUND;
Gulf Semiconductor
SBAV99LT1G
Onsemi
SBAV99LT1G by Onsemi is a rectifier diode with a max repetitive peak reverse voltage of 100V. It has a small outline package style and a fast max reverse recovery time of 0.006 us. It is commonly used in applications requiring low power dissipation and high operating temperatures.
ERJ2RKF1002X
Panasonic
Panasonic's ERJ2RKF1002X is a fixed resistor with 10000 ohm resistance, 1% tolerance, and 0.1 W power dissipation. Ideal for surface mount applications in automotive electronics due to AEC-Q200 compliance and operating temperature range of -55 to 155 °C.
Itt Components
RECTIFIER DIODE; Surface Mount: NO; Config: SINGLE; Maximum Operating Temperature: 200 Cel; Maximum Repetitive Peak Reverse Voltage: 100 V; Maximum Output Current: .15 A;
ULN2803ADWG4
ULN2803ADWG4 by Texas Instruments is a peripheral driver with 8 functions, open-collector output characteristics, and built-in transient protections. It operates at temperatures ranging from -40 to 85°C and has a max supply voltage of 3V. Ideal for applications requiring sink current flow direction in a small outline package style.
BSS138PS,115
NXP Semiconductors
NXP Semiconductors' BSS138PS,115 is a N-CHANNEL FET with 60V DS breakdown voltage and 0.32A max drain current. Ideal for switching applications, it features a 1.6 ohm max on-resistance and operates in enhancement mode. The transistor comes in a small outline package with GULL WING terminals, making it suitable for surface mount designs.
1N4148WS
Tak Cheong Electronics Holdings
RECTIFIER DIODE; Terminal Position: DUAL; Terminal Form: FLAT; No. of Terminals: 2; Surface Mount: YES; Package Shape: RECTANGULAR;
MMBT2907ALT1G
MMBT2907ALT1G by Onsemi is a PNP BJT transistor with 100 min hFE, 60V VCEO, and 200MHz fT. Ideal for switching applications, it has a small outline package with Gull Wing terminals and can handle up to 0.6A of collector current.
Temic Semiconductors
RECTIFIER DIODE; Terminal Position: END; Terminal Form: NO LEAD; No. of Terminals: 2; Surface Mount: YES; Package Shape: ROUND;
1N4148WT
Surge Components
MK06-7-B
Standex-meder Electronics
MK06-7-B by Standex-Meder Electronics is a proximity sensor with a body width of 3.3" and height of 4.2mm, suitable for applications requiring photoelectric sensors. It operates b/w -20°C to 85°C, housed in PBT glass fiber reinforced material with solder termination and through-hole mounting feature.
MK24-B-2-OE
MK24-B-2-OE by Standex-Meder Electronics is a 2.2" proximity sensor with a rectangular shape, suitable for surface mount applications. It operates b/w -40°C to 130°C, featuring mineral-filled epoxy housing and solder termination. Ideal for photoelectric sensing in various industrial environments.
59135-4-S-02-D
Littelfuse
PROXIMITY SENSOR,PHOTOELECTRIC; Mounting Feature: FLANGE MOUNT; Package Shape or Style: RECTANGULAR; Body Height: 3.43 mm; Termination Type: CABLE; Output Interface Type: 2-WIRE INTERFACE;
MK15-B-2-OE
MK15-B-2-OE by Standex-Meder Electronics is a 2.5" proximity sensor with a rectangular shape, operating b/w -40°C to 130°C. It features a mineral-filled epoxy housing, solder termination, and surface mount capability. Ideal for applications requiring precise photoelectric sensing in compact spaces.
59085-010
PROXIMITY SENSOR,HALL EFFECT; Mounting Feature: PANEL MOUNT; Maximum Operating Temperature: 105 Cel; Termination Type: CABLE; Minimum Operating Temperature: -40 Cel;
59070-4-T-02-E
PROXIMITY SENSOR,PHOTOELECTRIC; Package Shape or Style: CYLINDRICAL; Body Length/Diameter: 8 mm; Output Interface Type: 2-WIRE INTERFACE; Maximum Operating Temperature: 105 Cel; Termination Type: CABLE;
CR18-8DN
Autonics
Autonics CR18-8DN is a 3-WIRE DC, NPN, NO proximity sensor with a measurement range of 0-8.8mm. Operating b/w -25 to 70°C, it has a supply voltage range of 10-30V and max current of 15mA. Ideal for industrial automation applications requiring precise object detection in tight spaces.
XUB1ANANL2
Schneider Electric Sa
XUB1ANANL2 by Schneider Electric Sa is a cylindrical proximity sensor with NPN, NO output type. It operates at temperatures from -25 to 55 °C and has a max measurement range of 4000 mm. Ideal for applications requiring precise object detection in industrial settings.
VCNL4020-GS08
Vishay Semiconductors
PROXIMITY SENSOR,PHOTOELECTRIC; Mounting Feature: SURFACE MOUNT; Output Type: DIGITAL OUTPUT; Package Shape or Style: RECTANGULAR; Body Height: .83 mm; Minimum Measurement Range (mm): 1 mm;
STM8T143AM61TTR
STMicroelectronics
STM8T143AM61TTR by STMicroelectronics is a capacitive proximity sensor with 2.3V to 5.5V supply voltage range, digital output interface, and response time of 60ms. Ideal for surface mount applications in various industries due to its compact size (4.9mm x 3.9 inch x 1.75mm) and operating temperature range from -40 °C to 85°C.
H1522-005
PROXIMITY SENSOR,HALL EFFECT; Output Type: ANALOG CURRENT; Package Shape or Style: ROUND; Additional Features: TTL COMPATIBLE; Termination Type: CABLE; Body Length/Diameter: 1 mm;
59025-3-T-02-E
PROXIMITY SENSOR,PHOTOELECTRIC;
59065-4-S-04-D
PROXIMITY SENSOR,PHOTOELECTRIC; Package Shape or Style: CYLINDRICAL; Response Time: 3000 us; Maximum Operating Current: 250 mA; Body Length/Diameter: 8 mm; Maximum Operating Temperature: 105 Cel;
H1622-006
PROXIMITY SENSOR,HALL EFFECT; Output Type: ANALOG CURRENT; Package Shape or Style: ROUND; Body Height: 5.26 mm; Additional Features: TTL COMPATIBLE; Minimum Measurement Range (mm): .12 mm;
BI5-M18-VP4X/S1679
Hans Turck & Kg
PROXIMITY SENSOR,INDUCTIVE;
H1512-005
PROXIMITY SENSOR,HALL EFFECT; Output Type: ANALOG CURRENT; Package Shape or Style: ROUND; Maximum Measurement Range (mm): 1.52 mm; Termination Type: CABLE; Minimum Measurement Range (mm): .12 mm;
59065-1-V-02-A
PROXIMITY SENSOR,PHOTOELECTRIC; Package Shape or Style: CYLINDRICAL; Minimum Operating Temperature: -40 Cel; Response Time: 1000 us; Termination Type: CABLE; Maximum Operating Temperature: 105 Cel;
59060-1-U-04-F
PROXIMITY SENSOR,PHOTOELECTRIC; Package Shape or Style: CYLINDRICAL; Maximum Operating Temperature: 105 Cel; Minimum Operating Temperature: -40 Cel; Response Time: 1000 us; Body Height: 36 mm;
55100-2H-02-A
PROXIMITY SENSOR,MAGNETIC; Mounting Feature: FLANGE MOUNT; No. of Terminals: 2; Output Type: DIGITAL CURRENT; Minimum Operating Temperature: -40 Cel; Power Supplies (V): 3.75/24;
MK21M-1A66B-500W
MK21M-1A66B-500W by Standex-Meder Electronics is a 19" proximity sensor with a response time of 100 us. It operates b/w -30°C to 150°C, housed in epoxy resin for durability. Ideal for panel mounting applications requiring a photoelectric proximity sensor with 1-wire interface.
Partstack™ will investigate all reported instances of potential suspect/counterfeit part listings.
MK23-80-B-2
Standex-Meder Electronics
PROXIMITY SENSOR,PHOTOELECTRIC; Mounting Feature: SURFACE MOUNT; Package Shape or Style: CYLINDRICAL; Maximum Operating Temperature: 130 Cel; Minimum Operating Temperature: -40 Cel; Response Time: 100 us;
Meder Electronic Ag
PROXIMITY SENSOR,PHOTOELECTRIC; Mounting Feature: SURFACE MOUNT; Package Shape or Style: CYLINDRICAL; Minimum Operating Temperature: -40 Cel; Maximum Operating Temperature: 130 Cel; Response Time: 100 us;
MK23-35-B-4
Proximity Sensors;
MK23-35-B-1
PROXIMITY SENSOR,PHOTOELECTRIC; Mounting Feature: SURFACE MOUNT; Package Shape or Style: CYLINDRICAL; Maximum Operating Temperature: 130 Cel; Termination Type: SOLDER; Body Length/Diameter: 10.5 mm;
PROXIMITY SENSOR,PHOTOELECTRIC; Mounting Feature: SURFACE MOUNT; Package Shape or Style: CYLINDRICAL; Response Time: 100 us; Body Length/Diameter: 10.5 mm; Minimum Operating Temperature: -40 Cel;
MK23-35-B-2
PROXIMITY SENSOR,PHOTOELECTRIC; Mounting Feature: SURFACE MOUNT; Package Shape or Style: CYLINDRICAL; Body Length/Diameter: 10.5 mm; Response Time: 100 us; Minimum Operating Temperature: -40 Cel;
PROXIMITY SENSOR,PHOTOELECTRIC; Mounting Feature: SURFACE MOUNT; Package Shape or Style: CYLINDRICAL; Maximum Operating Temperature: 130 Cel; Body Length/Diameter: 10.5 mm; Response Time: 100 us;
MK23-35-C-2
PROXIMITY SENSOR,PHOTOELECTRIC; Mounting Feature: SURFACE MOUNT; Package Shape or Style: CYLINDRICAL; Body Length/Diameter: 10.5 mm; Minimum Operating Temperature: -40 Cel; Maximum Operating Temperature: 130 Cel;
PROXIMITY SENSOR,PHOTOELECTRIC; Mounting Feature: SURFACE MOUNT; Package Shape or Style: CYLINDRICAL; Termination Type: SOLDER; Body Height: 1.9 mm; Minimum Operating Temperature: -40 Cel;
MK23-35-C-4
PROXIMITY SENSOR,PHOTOELECTRIC; Mounting Feature: SURFACE MOUNT; Package Shape or Style: CYLINDRICAL; Body Length/Diameter: 10.5 mm; Body Width: 2.2 inch; Termination Type: SOLDER;
MK23-35-C-4 by Standex-Meder Electronics is a proximity sensor with dimensions 2.2" x 2.15mm x 10.5mm, operating b/w -40°C to 130°C. It features a cylindrical shape, solder termination, and surface mount capability. Ideal for applications requiring precise photoelectric sensing in various environments.
MK23-35-D-1
PROXIMITY SENSOR,PHOTOELECTRIC; Mounting Feature: PANEL MOUNT; Package Shape or Style: CYLINDRICAL; Body Width: 2.2 inch; Termination Type: WIRE; Maximum Operating Temperature: 130 Cel;
PROXIMITY SENSOR,PHOTOELECTRIC; Mounting Feature: PANEL MOUNT; Package Shape or Style: CYLINDRICAL; Termination Type: WIRE; Body Width: 2.2 inch; Body Length/Diameter: 10.5 mm;
MK23-35-D-2
MK23-35-D-2 by Standex-Meder Electronics is a cylindrical proximity sensor with a body length of 10.5 mm. It operates in temperatures ranging from -40 to 130 °C and has a surface mounting feature. It is commonly used in applications requiring photoelectric proximity sensing.
PROXIMITY SENSOR,PHOTOELECTRIC; Mounting Feature: SURFACE MOUNT; Package Shape or Style: CYLINDRICAL; Body Length/Diameter: 10.5 mm; Termination Type: SOLDER; Maximum Operating Temperature: 130 Cel;
MK23-35-D-4
MK23-80-C-2
PROXIMITY SENSOR,PHOTOELECTRIC; Mounting Feature: SURFACE MOUNT; Package Shape or Style: CYLINDRICAL; Response Time: 100 us; Body Length/Diameter: 7 mm; Termination Type: SOLDER;
MK23-87-B-2
PROXIMITY SENSOR,PHOTOELECTRIC; Mounting Feature: SURFACE MOUNT; Package Shape or Style: CYLINDRICAL; Minimum Operating Temperature: -40 Cel; Response Time: 100 us; Maximum Operating Temperature: 130 Cel;
PROXIMITY SENSOR,PHOTOELECTRIC; Mounting Feature: SURFACE MOUNT; Package Shape or Style: CYLINDRICAL; Minimum Operating Temperature: -40 Cel; Termination Type: SOLDER; Response Time: 100 us;
MK23-80-G-2
PROXIMITY SENSOR,PHOTOELECTRIC; Mounting Feature: SURFACE MOUNT; Package Shape or Style: CYLINDRICAL; Maximum Operating Temperature: 130 Cel; Response Time: 100 us; Termination Type: SOLDER;
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