The Yealink EXP50 Color-screen Expansion Module for Yealink T5 Series IP phones, including SIP-T58V/SIP-T58A/SIP-T56A/SIPT54S/SIP-T52S, is designed to expand the functional capability of your SIP phone to a whole new level. It features a large 4.3-inch color-screen LCD, giving you a vivid visual experience. In addition, it provides you with a simple user interface and advanced call handling capabilities. For example, three pages of 20 flexible button shown on the display can be programmed up to 60 various features. The functionality of Yealink T5 Series IP phones will also be extended by the EXP50, you can set the provided multifunctional line keys as BLF, speed dial, call forward, transfer, call park and call pick ups.