Garmin Astro Magnetic Mount Antenna - Tired of searching for your hunting dog in tall grass or dense cover?Now you can leave the hunting entirely to him. Introducing Astro, the first high sensitivity GPS-enabled dog tracking system for hunters and sportsmen. This unique system pinpoints your dog s position and shows you exactly where he is, even when you can t see or hear him. Powerful magnetic mount. Compatible Devices: Astro(R); Astro(R) 220; Alpha(TM);