A top-mounted, high-sensitivity GPS/GLONASS receiver, T 5 mini dog Device uses LED beacon lights activated from its compatible handheld device. The lights work in low-light conditions and at night, and are visible up to 100 yards away. Rugged and water-resistant to 10 meters, The tracking-only dog Device with collar is tough enough to run wherever your dog runs, up to 4 miles away. Package Dimensions: 8.382 L x 24.384 H x 19.558 W (centimeters)