Yealink SIP T42U. Product type: IP Phone, Product colour: Grey, Handset type: Wireless handset. Phonebook capacity: 1000 entries. Display: LCD, Display diagonal: 6.86 cm (2.7"), Display resolution: 192 x 68 pixels. Ethernet LAN interface type: Gigabit Ethernet, Supported network protocols: IPv4/IPv6, SIP v1 (RFC2543), v2 (RFC3261), UDP/TCP/DNS-SRV (RFC 3263), Security algorithms: 256-bit AES, HTTPS, TLS, WPA2, WPA3. AC adapter input voltage: 100 - 240 V, Input frequency: 50/60 Hz, AC adapter output voltage: 5 V