Vetoquinol Flexadin Advanced Dog Hip and Joint Supplement with UC-II Collagen, One Chew a Day Hip and Joint Support Chew for Dogs and Cats, Clinically Proven Vet-Approved Formula, 30 ChewsWhat is UC II A clinically backed proprietary form of type II collagen that works differently than chondroitin and glucosamine for dogs to help provide optimal joint support for your pet How Does UC II Work Our dog joint supplement works with your pet's immune system to help reduce soreness and discomfort caused by collagen that has loosened from wear and tear on the joints More effective than Glucosamine Our clinically proven and veterinarian