Accessory handset is designed for use with AT&T Dect 6.0 TL86109 Telephone System with Bluetooth capability. Dect 6.0 technology delivers up to 45 percent more range over 2.4 GHz and 5.8 GHz phone systems without needing a boost in power. Handset speakerphone leaves your hands free to do other things and lets more people in on the conversation. Intercom between handsets. Conference between an outside line and up to four cordless handsets. Two-line handset also offers high-contrast backlit LCD and lighted keypad, Caller ID/Call Waiting with a 200-name/number history, any key answer, volume control, last 20-number redial, and ringer volume control. Handset is headset compatible with its 2.5mm jack. Setup menu is in English, Spanish and French. Energy Star qualified.