Using your Aastra 55i, 57i & 57i-CT with Aastra 536M, call coverage and management is even more easy and efficient to handle. With the expansion module, you add additional programmable keys and LEDs, increasing your total number of keys and LEDs.

• Scalable to 3 expansion modules per phone
• Power direct from phone
• Programmable features: Line, speed-dial, BLF, BLA, SCA, DND
• 36-keys with LED
• Paper strip labeling
• Supported on 55i, 57i, 57i CT (Phone sold separately)