The M522 Expansion Module for M5316 Centrex phones adds 22 line indication/feature buttons to your phone. Up to two M522s can be added to your M5316. Requires either a single or double footstand, sold separately.
Remanufactured with one year warranty.
This model is also known as: M522, 522, NT4X, NT4X43, NT4X43CA, NT4X43AA, NT4X43BA, NT4X43KA