Features: 1.Voltage: 3.3 - 5V. 2.Output port: digital level signal. 3.Probe: microswitch. 4.Can be used for collision / contact inspection of robot or smart car, it also a limit switch for 3D printer or other smart devices. 5.Compatible with sensor expansion board. 6.Quick response and without delay. 7.Out: ( touch ) high level / ( release ) low level . 8.Module with mounting hole for convenient use. 9.Application: Arduino, singlechip, ARM and Raspberry Pi. 10.Come with a light transparent box for easy carry and store.