The TX-E221 is a Recessed Door/Window Sensor. Hidden within the door frame, this contact is virtually invisible when the door is closed making it ideal when discreet sensors are needed. The TX-E221 Recessed Door/Window Sensor uses a replaceable lithium battery that lasts up to five years under normal usage and comes with a standard flanged top
Features:
- Sensor is 3/4" diameter x 2.5" depth
- Magnet is 3/4" diameter x 1/2" depth
