The Krown Tactile Ring Signaler is designed especially for people with hearing and vision impairments by vibrating when there's an incoming telephone call. Includes one 8.4V rechargeable battery and AC adapter. Features: 80 feet range Alert indicators for visual, audio and vibration 9V rechargeable (battery and charger included) or 9V Alkaline for the receiver (pager) Works with VP200 and ZBox