The SportDog WetlandHunter 800 Dog Remote Training Collar is an incredibly versatile training collar and a excellent choice for all-around use. The Sportdog WetlandHunter SD-800 is great for training in the yard, field, or for hunting with medium range working dogs. Both the transmitter and receiver are waterproof and submersible. It can be expanded to control up to three dogs by adding SportDog brand add-a-dog collars. The comfortable soft coat transmitter finish makes this unit a pleasure to handle.The low continuous stimulation levels and gradual increases between levels on the SD-800 are particularly useful with sensitive dogs or breeds. You can customize your Sportdog wetlandhunter SD-800 to match your training preference. It comes set up in MODE-1 (an 8-level continuous + 8-level momentary stimulation one dog collar with a non-stimulation tone button), but it can easily be changed into 7 different modes with different button configurations. This allows you to customize your transmitter to your training needs. You are also able to transform your one dog system at any time into a two or three dog system using the add-a-dog feature.