Aastra M670i (536M) Expansion Module

Aastra M670i (536M) Expansion Module The Aastra M670i (536M) Expansion Module provides support for additional programmable keys. It provides 36 programmable keys and up to three expansion modules. Each button on the module has an LED status indicator that alerts users to the status of lines or extensions in a busy lamp field configuration. Features 36 keys with LEDs Connect up to 3 expansion modules per supported phone model LED Status Indicators Compatibility Aastra 57i, 57i CT, 6735i, 6737i, and 6739i Aastra 57i and 57i CT - no power supply required Aastra 6735i and 6737i - AC adapter is required if using more than a single expansion module Aastra 6739i - AC adapter is required if using any expansion modules (not included; see option below)