The FieldTrainer 400 Series is loaded with technical breakthroughs in the smallest package available in this price range. Features such as 3-dog capability and waterproof/submersible transmitters and receivers are among the most advanced features ever offered in a mid-range training system. With 400 yards of range, these palm-of-the-hand sized models are designed for field training and hunting with close-working dogs. The comfortable 'Soft-Coat' Transmitter finish makes these units a pleasure to use. And because we know that no two dogs are alike, we've designed the 400S model to provide higher stimulation power for larger or stubborn breed dogs.