Core Features: High-performance SIP cordless phone system, 1.8? 128 x 160 TFT color screen with intuitive user interface, Ruggedized DECT handset with IP54 protection rating, Up to 20 simultaneous calls, Up to 10 DECT cordless handsets, Up to 10 SIP accounts, Support Opus audio codec, Noise Reduction System, FNR (Flexible Noise Reduction)/Noise Cancellation, Up to 40-hour talk time, Up to 575-hour standby time, Quick charge: 10-minute charging time for 2-hour talk time,TLS and SRTP security encryption, Vibration alarm guarantees, Wall mountable charger, Up to 10 DECT cordless handsets and 10 SIP accounts, Up to 20 simultaneous calls to ensure that each handset can make two calls, Maximum DECT radio coverage: 50 meters indoors, 300 meters outdoors, Energy-saving ECO features.