FieldTrainerBoth the Transmitter and Receiver are waterproof, submersible, and camoflauge. It comes as a 1 dog system, but can be expanded to control up to 3 dogs by adding SportDOG Brand Add A Dog collars. The comfortable "soft coat" Transmitter finish makes this unit a pleasure to handle. Dog Training Gear the way you'd design it. 400 yards range Expands to 2 or 3 dogs Waterproof transmitter Waterproof receiver Realtree's Advantage Max 4 HD camo on all