Photo Beams, Wired Gate Exit Control, Operation Used to Provide a In.Non-Contact In. Means of Entrapment Protection. Range of 30ft Between Sender & Receiver. Normally Open or Normally Cloaed Wiring Options. LED's for Quick Alignment & Troubleshooting., Color Black, For Use With 29RV46, 13X161, 13X162, 13X156, 13X157, 36A984, 36A985, 36A982, 36A983, Includes (2) Photo Beam Devices