The EXP40 Expansion Module for the SIP-T46G and SIP-48G, expanding the functional capability of your sip phone to a whole new level. It features a large graphic LCD. Two pages of 20 flexible buttons are shown on the display can be programmed up to 40 various features, the productivity-enhancing features include BLF/BLA, speed dialling, call forward, transfer, park, pickup, etc. Up to 6 of the Yealink EXP40 can be daisy-chained together making it ideal for busy receptionists who need to be able to see who is available and transfer calls quickly and efficiently.