Combines the Astro 320 GPS with the DC 40 wireless transmitter collar. This unique DC 40 GPS system pinpoints your dogs position and shows you exactly where he is, even when you cant see or hear him. Strap the DC 40 wireless transmitter on your dog, and watch your dogs position transmit on the bright-color screen handheld GPS device. Signals transmit as often as every five seconds, so you can see his current location and a trail of where he has been. Dog Tracker page has a compass pointing to your dogs location, along with his current status whether hes running, sitting, on point or treeing. Track up to 10 dogs at a distance of up to nine miles (line of sight) with the purchase of additional collars. Astro can also sound an alarm to let you know instantly when your dog goes on point. Mark exact spots with the Covey Counter using the hunting-related waypoint icons. Contents include a bright-color screen handheld Astro 320 GPS with VHF antenna, a DC 40 wireless transmitter with collar, a vehicle power cable AC adapter, USB cable, a wrist strap and belt clip, an owners manual, quick reference guide, and a carry case. It also can be used as a standard GPS when not tracking dogs. It has all the features of Garmins top-line handheld outdoor devices, including a barometric altimeter, electronic compass, micro SD card slot, celestial information, area calculator and a rugged IPX7 waterproof exterior. The DC320 receivers simplified user interface and improved reception range of up to nine miles. The GPS unit with antenna is backwards compatible with DC 20, 30 and 40 model transmitter collars. The 2.6" LCD highly reflective 65K-color TFT supports enhanced Topo 24K and BirdsEye mapping. Other highlights include wireless unit-to-unit data transfer, auto-routing support, Hot-Fix GPS support, vibration alerts, built-in three-axis compass and barometric altimeter, and high-speed USB interface. Accepts Micro SD cards. Powered by two AA batteries (not included) for up to 20 hours.