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This rugged, waterproof tracking dog collar works with Garmin's Astro 320 dog-tracking system. The DC50 transmitter's upgraded steel VHF antenna improves durability and reliability, extending the effective range to nine miles and updating your dog's position every 5, 10, 30 or 120 seconds. Bark Detection allows you to know your dog is barking even out of audible range essential for running or treeing hounds. Top-mounted high-sensitivity receiver improves location performance. Rescue mode extends battery life, allowing you to catch up with even the most far-ranging dogs. Comes attached to an adjustable bright orange polyurethane collar but can also be attached to any standard 1" collar. Powered by a rechargeable lithium-ion battery. Includes Collar Lock with four-digit PIN to prevent others with Astro receivers from tracking your dog. Additional dog collar transmitters can be purchased to track up to 10 dogs at a time with your Astro dog tracking system. 8 oz. with battery. Imported.