zBoost YX545 SOHO Dual-Band Cell Phone Signal Booster for Home and Office up to 2,500 sq. ft. of Coverage Portable Consumer Electronics Home Gadget Extends cellular coverage for single or multiple users in homes or offices--provides up to 2500 Dual-band device works with 800/1900 MHz frequencies from all major carriers--AT&T, Sprint, Omni-directional signal antenna receives signals from multiple cell towers Antenna can be installed outdoors above the roofline or indoors in the attic or near a window Extends phone battery life--uses less power when signal is stronger