The rugged, versatile SportHunter Series from SportDOG excels in all environments and is especially suited to upland and multi-dog hunting situations. With the comfortable "soft coat" transmitter finish, these units are a pleasure to use. Both the transmitter and receiver are completely waterproof and submersible. The lightweight collar receiver features a slim-profile and contoured shape that ensures a custom fit on the dog's neck. No matter what style of training you prefer, this system can provide it. 1/2-mile range. DRYTEK waterproof and submersible to 25 feet. Expandable up to 3 dogs (with additional collars). 7 instantly-selectable stimulation levels. Tone and vibration option. Rechargeable batteries.