For hotels looking to provide a door knock alerting solution for guests who are deaf or have a hearing loss, this kit includes the CA360H Receiver with built-in dual alarm clock and bed shaker, plus the CA-DXH door knock signaler that hangs on the interior door knob - no over-the-door clip that's visible from the hallway!
CADX - Door Chime / Intercom and Door Knocking Sensor Accessory
The wireless Doorbell/Door Knock and Door Chime Sensor is part of the CentralAlert Notification System by Serene Innovations. It sends to the CentralAlert receiver to notify you when someone rings your doorbell. The CADX sensor can also be attached to the inside of your door to detect door knocks.