Can be used as 1 dog or 2 dog remote dog training collar system;(This listing is for 1 dog training) Corrective shock or vibration can be used for one dogs or two dogs; 2 Levels of shocks(low or high); Strong vibration to get any dog's attention; Rechargeable water-resistant receiver collar with long and short prongs for all coat types; Range of up to 600 yards (approx. 550 meters) and signal can pass through obstacles such as walls and fences; Suitable for healthy dogs of over 6 months old; Brand new and packed in a convenient carry-and-go storage bag; 1 Year manufacturer warranty.