Dr Tech Cell Phone Wireless Signal Booster for Home or Office , 2G 1900MHz , for T-Mobile US , GSM (1850-1910 1930-1990) , Single Band (1850-1910 1930-1990) , For At&T 2G & 3G 1900MHz GSM ;For Sprint 3G & 4G 1900MHz CDMA LTE WiMax;For T-Mobile US 2G 1900MHz GSM ;For T-Mobile US (MetroPCS) 2G 1900MHz CDMA LTE;For Verizon Wireless 2G & 3G 1900MHz CDMA;For US Cellular 2G 1900MHz GSM The function is to send signal from base station to the indoor coverage directly, and through the small base station antenna. reliable signal to small regional coverage for indoor coverage results achieved marginal field above - 75dBm. ALC ensure output level stable and adjustable continuously;Low power consumption and avoid to interference to BTS. LED indicate and judge to signal level of uplink and downlink. With the amplified linear power, the intermodulation and and spuriousness are suppressed effectively. To easy or and convenient installation.