Product Name: Proximity Switch Sensor; Model: SN04-N; Type: DC 3-wire NPN NO; Inductance Sensor Output: Switching Transducer; Sensing Distance: 4mm; Working Voltage: 10-30V DC Response Frequency: 500Hz max; Indicator: Red LED; Size: 18 x 18 x 36mm / 0.7" x 0.7" x 1.4" (W*H*L) Cable Length: 135cm / 53"; Hole Size: 0.9 x 0.4cm / 0.35" x 0.2" (L*W); External Material: Metal Net Weight: 48g; Color: Black, Green Over-current and short circuit protection with LED indicator for easy identification The proximity sensor switch is used for detecting parts such as size and speed, and can also be used in frequency counters, frequency pulse generators, liquid level control, and automated processing applications Package Content: 1 x Proximity Sensor Switch, 4 x Screws Note: Lighting and different displays may cause the color of the item in the picture to appear slightly different from the actual product. Measurement allows an error of +/-1-3 cm