The Venture Series™ Big Dog Add-A-Dog® will work with any Venture Series™ Training System. It programs in seconds and converts your 1-dog system into an easy-to-use 2 dog system. The collar provides a range of 900 m (1000 yd), 8 stimulation levels, and a remarkably thin and comfortable design. It is designed for dogs over 18 kg (40 lb).