Until now, most signal boosters were either dual-band and only boosted 3G and earlier signals or they were 4G LTE specific and only boosted the LTE signal which doesn't support voice calls.Wilson's 805370 Tri-Band 4G-A is the first ever consumer wireless signal booster designed specifically for the AT&T Wireless 2G, 3G and new 4G LTE networks.The Wilson 805370 Tri-Band repeater for AT&T features a 70 dB gain which gives it a total coverage area of up to 10,000 sq ft making this the ideal amplifier for large homes and small to medium offices. Because this is a powerful amplifier, you must have a minimum of 20 ft of vertical separation between the inside and outside antennas. Adding up to 75 feet of horizontal separation can help improve the performance of this signal booster by minimizing the potential for oscillation (feedback) between the inside and outside antennas.