Nylabone Durable Chew Bone. Designed To Satisfy The Chewing Instinct Of Aggressive Chewing Dogs. Nylabone Durable Chew bones are recommended for teething puppies and powerful chewing dogs.We've indicated which size may be appropriate by dog's weight.** Sizes: Petite for dogs under 8 lbs., Regular for dogs 8 to 20 lbs., Wolf for dogs 20 to 45 lbs, Giant for dogs 45 to 65 lbs. and Souper for dogs over 65 lbs.