Perfect for monitoring an entrance or for use as an entrance indicator;No hard wiring required, all components plug into each other;Standalone system includes reflector, adapter, sensor and chime;Photoelectric beam sensor;Two tone choices - siren and ding dong

• Seco-Larm E-931CS22RRCQ Enforcer NIR Retro-Reflective Entry Alert System, Up to 22ft Range

Seco-Larm E-931CS22RRCQ Enforcer NIR Retro-Reflective Entry Alert System, Up to 22ft RangeSmarthome Technologies