Features: 1.High Sensitivity: The lens type optical element strengthens the beam intensity, has good immunity to false alarms caused by rain, snow, fog, etc., highly convenient to use. 2.Low Battery Reminder: When the battery is low, the red LED on the transmitter side will flash, and the receiver's buzzer will sound every second to remind you to replace the battery in time. 3.Wide Applications: Provides invisible infrared beams for automation applications such as sliding and swinging doors, garage doors and security applications, outdoor or indoor fencing, etc. 4.Waterproof Protection: Infrared gate beam sensor is IP55 waterproof, can be installed indoors or outdoors, small size, easy to install, does not affect the normal function of your device. 5.Durable Structure: Infrared gate beam detector is made from superior ABS, wear resistant and durable, the transmitter is powered by 2PCS AA batteries (not included), and the long life can reach about 2 years. Specification: Item Type: Infrared Gate Beam Sensor_x000D_ Material: ABS_x000D_ Application: Home security, access control system_x000D_ Working Voltage: _x000D_ Receiver: 12-36VDC_x000D_ Transmitter: 3V (2PCS AA battery, NOT included)_x000D_ Installation Environment: Indoor, outdoor_x000D_ Detection Distance: Approx. 15m / 16.4yd_x000D_ Alarm Time: 3s, 5s, 10s adjustable_x000D_ Alarm Output: Relay contact output NC, NO_x000D_ Contact Capacity: 30V DC 3A maximum 250V AC 3A maximum_x000D_ Battery Life: About 2 years_x000D_ Wavelength: 940nm_x000D_ Modulation Frequency: Pulse_x000D_ Waterproof Grade: IP55_x000D_ Single Product Size: Approx. 136x54x32mm/5.4x2.1x1.3in_x000D_ PackageList: 1 x Transmitter 1 x Receiver 4 x Screw 4 x Expansion Tube 1 x Manual