CentralAlert Door Knock Sensor Model CA-DX

Install device on existing door chime or intercom door announcer for vibration detection. When someone rings your door bell, it detects vibration and sends a wireless signal to trigger the CA-360 to alert. Or, you can attach the CA-DX to the inside surface of your door to detect the knocking on your door.

Product Features: 

• Detects vibration form existing doorbell or door chime and sends signal to CA-360 when someone is at the door
• Attach to or place near existing doorbell or door intercom
• 2.5mm jack for direct connection to doorbell terminal
• Optional door-knob hanger for hotel kit
• Sensitivity adjustment