Cell Phone Signal Booster for All Carriers GSM 3G - Dual Band 850/1900MHz Band 2/5 Repeater Boosts Voice and 3G Data for Home and Office

Frequency Range: Band 2, Band 5 Max. Gain: 65dB Max. Output Power: 20dBm Automatic Gain Control: ?20dB I/O Port: N-female Impedance: 50 ohm Power Supply: Input AC 100~240V 50/60Hz, Output DC 5V The booster can only amplify signal but cant create signal, please make sure there is at least 1-2 bars signal outside, otherwise it will not work.The booster doesnt works allow, it should work together with indoor antenna and outdoor antenna.The booster only supports cell phones on band 2 and band 5, please check which band your cell phone uses firstly by the methods below:Dial *3001#12345#*, then press Call button, Click Serving Cell Info, then Check Freq Band Indicator;Download and install the app: LTE Discovery, tap ‘SIGNALS’ and check band number.