The Omron E3ZM-T81 2M Photoelectric Sensor offers Square type, Through-beam , 15 m Sensing distance, NPN Output, Pre-wired cable length 5m, 10 to 30 VDC Power Supply Voltage. Manufactured by Omron under the Omron Photoelectric Sensors category, this model belongs to the Omron E3ZM Series and includes an Emitter (E3ZM-T81-L 2M) and Receiver (E3ZM-T81-D 2M), it utilizing a Infrared LED Light source, Light-ON/Dark-ON mode.