The Walk’r Unique Sensor detects the amount of pressure on the leash. Intelligent activator turns on when the dog pulls extra hard on the leash; but doesn’t turn on during normal activity. Patented motivational process adjusts the amount of correction to match the dog’s abnormal pull on the leash. Three user-selectable levels of correction. Water-tight; heavy-impact; plastic housing. 32 inches long; one inch wide nylon collar strap with metal buckle included. 3-volt lithium battery (thousands of activations) Non-rechargeable user replaceable battery. Weight: 8 oz. (housing; collar strap and battery). 7 minute “Electronic dog training leash” demonstration video CD. Made in the U.S.A.