Additional 22 direct dial keys
The Nortel Meridian M3900 KBA (Key Based Add on Module) is AOM designed for the Nortel Meridian M3900 telephone series. The M3900 KBA will provide an additional 22 direct dial keys and matching BLFs.
A total of two M3900 KBAs can be added to the 3900 series telephones, giving a maximum of 44 programmable keys. This model is compatible with the M3904 and M3905 telephones.