Seco-Larm E-931CS22RFCQ Enforcer Wireless Door Entry Alert With Chime

Wireless Entry Alert System, 433MHz, Wireless Speaker and Sensor For monitoring a driveway or use as an entrance indicator. No wiring required between the sensor and speaker; when tripped, the sensor wirelessly transmits to any programmed speaker. Weatherproof photoelectric beam sensor for outdoor use. Speaker makes "ding-dong" or siren sound if beam is interrupted. Speaker volume can be adjusted or turned off. When in siren mode, sounding time is adjustable from 3~30 seconds. Connect additional speakers to the sensor wirelessly (one speaker included).