Model FC-33 Quantity 1 Color Black + silver Material PCB Features It outputs low level when there is not block in the groove otherwise it output high level. The output end can connect to power relay to form normal limit switch function or connects to active buzzer module to form alarm. Specification Groove type optocoupler sensor groove width: 10mm; With output state indicator it lights on when output high level and off when output low level. Working voltage: 3.3~5V current>15mA 0/1 output; Comparator: LM393 Application Widely use for test motor speed work piece counting etc. English Manual/Spec Provides cable connecting manual Packing List 1 x Module