The X4U is a next-generation (an updated model of X4) and feature-rich sip phone for business. The 12 SIP Line IP Phone with 3 Line Key has been designed by pursuing ease of use in even the tiniest details. Dual 10/100/1000 Mbps network ports with integrated PoE are ideal for extended network use. Delivering a superb sound quality (Harman Kardon Speaker), supporting Opus Codec, as well as a rich visual experience. With the second DSS color screen, the IP Phone supports up to 30 DSS keys which improve work efficiency. Using standard encryption protocols to perform highly secure remote provisioning and software upgrades.