GSM Fixed Wireless Terminal 5V 1A Quad Band Strong Receiving Ability Wireless Terminal Caller with Backlight Screen 100‑240V UK Plug Item Type: GSM Fixed Wireless Terminal Material:ABS Product Size: Length x Width Approx. 15.5 x 10cm / 6.1 x 3.9in (Manual Measurement, There Will be 0-1cm Error) SIM Card: No Need to Invest in Ground Wire Line, Use GSM Mobile Phone SIM Card. Easy to Install Support Business: Support International and Domestic, Local, Fixed, Mobile Voice Services Operating Habits: Do Not Change the Original Dialing Habits, the Same As Ordinary Telephone Landline Operating Habits Reverse Polarity Signal: with Reverse Polarity Signal, Can Be Connected to Meter or Use Computer Meter Automatic Detection: Built in Watchdog Duty Circuit. Automatic Detection of Equipment Running Status, Automatic Restart in Case of Failure Transmission Mode: DTMF Transmission Mode, Caller Id 0 Error Function: Fully Automatic Ip Function, Multiple Sets of Ip Settings Ip Prefix: the Calling Ip Prefix Automatically Inserted by Fixed Toll, Such As 17951, 17911, 193, Etc. Permission Setting: Various Permission Settings for the Called Party, Such As International, Domestic and Local Calls Default: Default Local Area Code, Local Number Segment and Prohibited Number or Number Segment Encryption Settings: Encryption Settings, Such As PIN Code, PUK Code Encryption Machine Card Lock Function LED Lights: LED Lights Display Information Such As Signal, Standby Status, Working Status, Etc. Caller ID: Yes Interface Form: RJ11 Network Support: GSM: 1900 1800 900 850M Visual Function: None Scope of Application: Wireless Access, Security Number Storage Function: Yes Recording Function: None Network Parameters GSM: 1900 1800 900 850M Signal Sensitivity: < -104DBM Transmit Power: <2W Antenna Power: >1.5db Power: 5V 1A Device Power: <5W RJ11 Dial Audio Frequency: 450HZ RJ11 Feed Current: 20MA to 40mA RJ11 Reverse Polarity: Support RJ11 Call System: DTMF Working Environment Temperature: -20℃ to 50℃ Relative Humidity of Working Environment: Humidity 10 to 90%