Grandstream GS-GXP2200EXT Expansion Module for VoIP Phone

Large 128x384 graphic LCD providing feature-rich graphics Daisy-chain 4 modules for up to 160 programmable buttons 2 page switch keys which allows up to 40 extensions per extension module 20 programmable buttons per module Busy Lamp Field (BLF)You may also like Grandstream Networks GRP2613 The Grp2613 Is A Powerful 3-line Carrier-grade Ip Phone Designed With Zero-touch.