VOIP Phone 4G WiFi 2.4 Inch Color Display 3 Lines Multi Function Wireless Landline for Office Business 100‑240V EU Plug Item Type: VOIP Phone Material: ABS Model: S01 SIM Card: Support Standard SIM Card (Not Included), 2 x Card Slot LCD Display: 2.4 Inch Color Screen Keys: 3 x 4 and 25 Keys WIFI: Support 802.11b/g/n Charging Interface: Micro USB Charging Interface Network: 4G Full Netcom Frequency: FDD LTE: B1, B3, B7, B20, B28A TDD LTE: B38, B39, B40, B41 WCDMA: B1, B2, B5, B8 GSM: B2, B3, B5, B8 BT: 4.0 Battery: 1000mAh Li Ion Battery (Included) Fast Dial: M1 to M3, 2 to 9 Numeric Keys Phonebook: Support 500 Contacts Call Records: Support 50 Records Voicemail: Reminder of Unread Voicemails Phone Function: Add, Delete Contacts, Missed Call Alert, Do Not Disturb, Automatic Answer, Call Transfer, Busy Transfer, Unconditional Transfer VOIP Parameters: SIP Protocol: SIP 2.0 (RFC3261) Transport Protocol: UDP, TCP, TLS Support 3 Way SIP Account DTMF Capabilities: RFC 2833 and SIP INFO Sound Codec: G.722, G.729, AMR, AMRWB, GSM, PCMAPCMU, SPE EX, ILBC, DTMF, ISACWB, for OPUS Sound Functions: AEC, AD, CNG, AGC, ANS 3GPP: TS 24.605 Call Forwarding: Support Stun: Support SIP Lines: 3 Lines Introduction: S01 4G fixed telephone is a multi functional communication terminal, which is a VOIP terminal product with strong practicability and strong manageability for IP network voice communication. It can be used for extended and network IP telephony operation networks within the enterprise and has Internet access. It can be connected to the operator 4G network, and with the support of the operator, the communication cost is extremely low. It can also be used as a communication tool, is cost effective, has high stability, and is most compatible with traditional usage habits in various private networks.