Know your gear
The expansion module for the FON-450i/FON-550i phone provides 12 additional line/programmable feature keys. You can place the phone and expansion module on your desktop or you can wall-mount them.
Up to two expansion modules are supported on a single phone. The expansion modules work with the FON-450i and FON-550i phones.
Up to two expansion modules are supported on a single phone. The expansion modules work with the FON-450i and FON-550i phones.