AT&T TL7700 - Manual (Page 12)

8
Getting started
Add and register headsets
You must register your new TL7700 headset with a compatible
AT&T DECT 6.0 telephone before use (see page 9). The telephone
base recognizes and counts a headset the same as a handset.
Refer to your telephone user’s manual for the maximum number
of handsets and headsets that you can register to the telephone.
If you have the maximum number of handsets registered, you
need to follow the deregistration information in your telephone
user’s manual before you can register a headset. Visit
www.telephones.att.com
for a list of compatible telephones.
You can only register the headset to one product at a time. You
must deregister the headset before registering it to another
telephone (see page 10).