My dog love chewing on a smoked dog bones in the back yard. He can sit there for hours on end just working away at a bone. I remember this one time I gave him a large bone and remember it took him practically all summer to chew through the entire thing. Of course those big bones are a bit large for my dog which is why for his special treat I like to give him these knuckle bones because while they may not last as long, they better serve the purpose of being a treat and not something he can expect all the time.