The new RC-8 collar is compatible with all Humane Contain electronic fences by High Tech Pet Products and also works with our Radio Mat pet deterrent transmitter pad. The RC-8 is the most advanced radio dog containment collar made. This powerful collar weighs only 1.3-ounce., and has features not found on any other radio collar. No other collar features the built-in stimulus test lamp that lets you test your boundary field and functionality of the shock output without using an external test lamp. The collar's internal computer chip tells you the operating condition with a continuously flashing LED. This fully-waterproof collar contains a water-sealed speaker that transmits sound directly to the outside world (whereas other collars use casing around the speaker). This means that the RC-8 gives you louder, more reliable training tones for faster boundary training. The nearly indestructible poly-elastomeric strap integrated with the electronics casing gives you the most high tech electronic collar at an amazing value. This ultra-slim, lightweight and comfortable collar is adjustable from 7-inch to 25-inch for all dogs 5-pound and up. Comes with short hair and long hair probes. Uses one long-life replaceable battery (model B3V8-1P).