The Alpha 100 Handheld operates as a high-end GPS unit when your adventures take you far from the road, and it doubles as the centerpiece for the Alpha Dog Tracking and Training System. Used as a dog tracking/training device, it tracks up to 15 dogs wearing TT 10 Collars (not included). Its interface puts you in charge of 18 levels of momentary and continuous collar stimulation, and it delivers hunter-to-hunter positioning reports. Pre-loaded with 100K TOPO for the United States so you’ll know exactly where you are, how to get to your destination and what topographical obstacles stand in your way. The 3", sunlight-readable, glove-friendly touch-screen display features an intuitive user interface with three quick-reference buttons. The barometric altimeter tracks changes in pressure to pinpoint your precise altitude and monitor weather conditions. The three-axis compass provides accurate headings at all times. High-sensitivity Quad helix GPS antenna with HotFix™ secures a strong, fast signal. Able to support ANT+™ for unit-to-unit wireless transfer of data between other handhelds and advanced mapping, such as BirdsEye™, 24k maps and custom maps. Tone and vibration alerts. Uses a MURS frequency band, which is not compatible with the Astro® series. Includes a rechargeable lithium-ion battery pack that lasts up to 16 hours under typical use.