This device prevents the phones from ringing on incoming calls. The calling party just hears the phone ringing and ringing, but it's never answered since the phones are silent on the target's end so they have no idea that someone is calling them.

Like the device above, this unit prevents the phones from ringing during incoming calls. The target has no idea that someone is calling, and so they'll miss all of their calls.

The Telephone Voice Transformer meets the requirements of the law enforcement professional to realistically and effectively disguise their voice in real-time telephone applications.