** Important: this product requires an external/outdoors antenna with F-cable connectivity to operate (not included in the package due to transportation difficulties caused by its size ** . - Design to amplify GSM 900 cell phone signals and to extend cell phone coverage to areas that have poor or no cell phone signal (such as basements underground parking concrete structures etc) - Signal gains: >=45dB upstream>=50dB downstream (manufacturer rated) - Signal output: >=20dBm (manufacturer rated) - Indoors antenna included - Wall-mount kit included - Requires outdoors antenna to operate (F-cable connector) - Works for 890~960Mhz signal range - 100~240V AC adapter included . * Warranty information is located in the specifications section