The SportDog Field Trainer Add-A-Collar Stubborn Dog Model has a low profile design which makes it perfect for smaller dogs. Do not let the 4.8 ounce size fool you, this 100 % waterproof collar has over a 400 yard range. This Add-A-Dog-Collar will work with the following models: SD-400, SD-400S, SD-1200, SD-1800, SD-2000 and SD-2400.

Features: Weight: 4.8 ounces with collar Receiver Dimensions 2.5" x 1.5" x 1.25" High output FREE biothane style green strap FREE dual charger Internal antenna system Rugged molded design 100 % Waterproof Collar/Receiver Rechargeable NiMH batteries User-replaceable, heavy duty battery Battery lasts 3-5 years with proper care Built-in LED - acts as charging light, test light