Photocell Infrared Safety Beam Sensor for Automatic Gate & Security Alarm System

For Shimano Altus M310 RD-M310 7/8 Speed Rear Derailleur Hangar Mount Device. 1 x Single Beam Infrared Sensor Transmitter. 1 x Single Beam Infrared Sensor Receiver. Infrared frequency 1.92Khz. For Gate Automation, Barrier And Security Alarm Systems.

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