Features:
- 22-button expansion unit
- Up to 2 expansions can be used per phone
System Requirements/Compatibility:
- Compatible with both the M5216 and M5316
- Requires one of the following:
- Single footstand (7801xx) for one add-on
- Double footstand (7802xx) for 2 add-ons
*xx equals color code 35 ash, 03 black and 93 gray
Product shown in Black.