These fresh-tasting, one-of-a-kind rope bones contain actual dental floss twisted in with all-natural cotton fibers. In addition, the BOODA® Fresh N' Floss™ contains baking soda and fluoride to fight plaque and control tartar. All this and these rope bones are non-evasive and non-irritating to sensitive mouths and gums. The medium rope bone is about 6" between knots, made of thicker rope than the small bone and is best for dogs 18 to 44 lbs.