"Yealink Ruggedized DECT IP Phone System • High-performance ruggedized SIP cordless phone system • Ruggedized DECT handset with IP54 protection rating • 1.8"" 128 x 160 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 • Noise Reduction System • FNR (Flexible Noise Reduction) •Up to 40 hours of talk time •Up to 575 hours of standby time • Quick charging: 10-min charge time for 2-hour talk time • TLS and SRTP security encryption • Vibration alarm gurantee you not to miss any call even in noisy situations • Charger wall mountable with PSU"