Now featuring adjustable gain to simplify installation! The cellular signal booster is dual-band (800 &1900 MHz) wireless amplifier for use in homes, offices and other buildings. It significantly improves voice and data performance for multiple cell phones and data cards simultaneously, and works with all major North American cell phone carriers, which include both Cellular (824-894 MHz) and PCS (1850-1990 MHz) carrier frequency bands. This 65 dB in-building booster combines high performance with ease of installation, and it can be used with an outside directional high gain antenna or omni-directional antenna with that eliminates researching cell tower locations and antenna orientation.