... CE approval, no radiation MMcall wireless emergency call button, nurse call button, alarm call buttonMMcall wireless nurse call system/ ... Transmitter: 1-key, 2-key, 3-key and 5-key call button with different functions2. Hub Center: Receive and transmit the ... .4. Optional: Monitoring system, multi transmitter, repeater, button stand.Different color necklace for your choice wireless emergency call ...