High Contrast White Backlight * Choose from 4 preset profiles * Accessory handset only * HD Audio Taking sound quality to the next level * For use with AT&T models CL81101, CL81201, CL81301, CL82101, CL82201, CL82251, CL82301, CL82401, CL82451, CL82501, and CL82601 (sold separately). Use up to 12 handsets through a single phone jack.