Ergonomically-designed collar is smaller, lighter and more comfortable. Exclusive ReadyTest® and PerfectFit tests ensure the Reciever Collar is ready and working. Anti-Linger Prevention stops dog from lingering in the warning zone and draining battery. Pass-through receiver allows you to use any length of collar strap that is non-metallic and 1.9 cm wide. For dogs 2.3 kg and up. Fits neck sizes 15 - 71 cm. 5 adjustable levels of static stimulation. Tone-only mode alerts your pet with a beep. Over Stimulation Protection: Stimulation stops after 15 seconds. Run Through Prevention- Static Stimulation increases if your dog tries to run through the boundary zone. Waterproof. Uses rechargeable batteries. Each charge usually lasts 3 months. Battery recharges in 2-3 hours. Low battery indicator. Compatible with YardMax In-Ground Fence™ system.