A BarkButler Chew Series. Chu the Bone is a 100% non toxic tested Premium Quality Natural Rubber Bone, it is durable and can hold treats. Designed to aid in teething, and be gentle on the gums. Playing Styles : Holds Jerkies,Fetch, Tug, Tough Chewing. Chu works best with Medium (10-20 kg) & Large (20-30kgs) sized dogs.