Tracker collars are available for different dogs and are equipped with various features and properties: bark indicators for chasing dogs, tree indicators for coon dogs and pointing mode for bird dogs. We even have available a tree and bark collar. They also offer a smaller collar designed for beagles. Batteries are a snap to change, and the Day-Glo collar guarantees durability and long life. These collars run on two 3.6V Lithium Batteries which are included.