Digital Antenna 824-894/1850-1990 MHZ (cellular/PCS) dual band 50 dB & 70dB home, office, marine and RV wireless cell boosters are designed to offer high gain with less antenna separation. It boosts the signal strength of your cell phone or air card to 3 watts and improves transmit and receive signals. All needed accessories are included. Not for use in open console boats. Wireless operation. No physical connection to cellphone, Enhances data connection for improved internet, fax and text messaging, Amplifies cellular signal up to 30+ miles, Extends the life of the battery of your device, Works with all 850/1900 MHz cell phones or air cards operating on any modulation including CDMA, GSM, TDMA, PCS, EV-DO, 3 watt dual band 40 dB or 70dB gain cellular repeater, 18" external 9dB gain antenna, Requires 12' (4KMR-30M) or 25' (4KSBR-50M) separation, plus a complete structure between inside and outside antennas.