manufacturer: OPTEK
manufacturer part number: OPB 822S
This optointerrupter contains an LED and a phototransistor separated by a slot. Devices like this are used to detect position, door closings, motor/wheel RPM, etc.

This is a DUAL Optointerrupter - 2 slot interrupters in one package. Through-Hole PCB leads with a 2 hole mounting flange.
QTY: 1 x Dual Opto-Interrupter (Two Pictured)