This mobile signal booster amplifier improves 2G, 3G, and 4G GSM 900MHz signals for clearer calls and stable connections. Designed for indoor use, it provides coverage up to 150 square meters with high gain performance. Easy to install, the system connects outdoor and indoor antennas through the repeater unit and automatically adjusts output levels with ALC technology. Built with full-duplex and dual-port design, LED indicators for signal status, and CE and RoHS approval, it ensures reliable operation in homes, offices, or small shops.