When the modern business world demands greater time efficiency from your already busy schedule, use the ability of the Berkshire 400 to automatically dial your often used numbers direct from memory. A few simple keystrokes will allow you to store a maximum of twelve telephone numbers into permanent memory (no battery required). Combine this memory with all the features of the Berkshire 200 and you have a fast, easy to use communication tool at your finger tips again with a worry free 10 year warranty. - MF Dialling - Latching Mute - Last Number Redial - ELR /TBR Switchable - RI / MW Switchable - Adjustable Ringer Volume - Adjustable Ringer Pitch - Modem Port - Headset Port - Adjustable Headset Volume - BT Line Cord - RJ45 Line Cord - Hearing Aid Compatible - Memories - 12 - External Memory Programming Port - Memory Disable Switch - Pause Key