Whistle Tagg Pet GPS Plus - Dog and Cat Tracker Collar Attachment Find Them Quickly If They Get Lost - The Tagg GPS Pet Tracker lets you set your pet's home zone and notifies you if they wander off using its award winning GPS location tracking system. Nationwide Coverage - Tagg uses cellular and GPS technology to pinpoint your dog's location anywhere in the U.S. Text & Email Alerts - On-demand notifications via app, text and email alerts when your pet gets out. Maps & Directions - If you ever need it, Tagg provides maps and directions so you can find your pet quickly and easily. Keep Them Healthy - Track your dog's activity and rest, getting key insights about their behavior and health Air Temperature Sensor - Tagg monitors your pet's surroundings and alerts you when they get too hot or cold (feature released in Autumn 2015) Dog Proof: 10-Day battery life, waterproof, and durable Device requires a service plan as low as $6.95/month to be selected at activation.