The Astro 320 is durable and waterproof thanks to the rugged casing. Buyers can choose between the full GPS plus collar package or just the GPS device. The DC 40 collar can provide position updates as frequent as every 5 seconds and has a battery life of up to 48 hours depending on settings. Other features include a four-digit pin that only allows you to track the dog, and an LED charging indicator. The Garmin Astro 320 is a good option for those with sporting dogs or just people who like to take their dogs out to the open. It is an expensive but reliable system to keep track of the location of your dog.