Keep your cell phone safe and dry by pairing it with this unit via Bluetooth® wireless technology. Unit installs and sets up in as little as 30 minutes and doesn't require that you recharge or replace batteries. Adjustable Volume can be set or controlled during calls with ease. Optional VOX with a dedicated button provides hands-free speakerphone mode. Noise-canceling microphone blocks background noise. Submersible to JIS7 standards. Caller ID lists up to 50 calls. Pairs with up to eight different mobile phones.