Keep your dog healthy and have fun together. Designed with vets. Works with easy-to-use app. Accurately measures and displays daily dog exercise and rest, distance and calories. Manages weight. Get personal breed-specific recommendations. Set and track goals. Win fun achievement badges. Fits any dog and collar/harness. Super-robust, feather-light, comfortable and fully-waterproof. Ultra-long (1+ years) user-replaceable battery (CR2032) included. No recharging, ever.