Core Features: High-performance SIP cordless phone system. 2.4? 240 x 320 TFT color screen with intuitive user interface. Up to 20 simultaneous calls. Up to 10 DECT cordless handsets. Up to 10 SIP accounts.Support Opus audio codec. Flexible Noise Reduction (FNR)/Noise Cancellation. Up to 21-hour talk time (in ideal conditions). Up to 166-hour standby time (in ideal conditions). Quick charge: 10-minute charge time for 2-hour talk time. TLS and SRTP security encryption. Headset connection via Bluetooth or 3.5 mm jack. Vibration alarm. 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.