1.Composed of Flexible Neoprene2.Perfect for Dogs in Recovery, Helps Prevent Operation and perfect for Older Dogs Providing full Joint Support and less knee stress.3.Features Surrounding Reflective Lining Strips4.Velcro Closures for Easy On and Off access5.Comes as a Set of 4. Patent PendingThe Extreme-Neoprene Patented Joint Protective Reflective Pet Sleeves are composed of lightly flexible Neoprene. These Pet Sleeves are perfect for all pets in operation recovery and further help prevent joint operation. These sleeves are designed and engineered to place less stress on your pets knee joints and are essential for all older dogs, puppies and even cats. Features Surroundable Reflective Lining for added protection during night walk and are perfect for those active dogs. Features Velcro closures for easy On and Off access. Comes as a set of 4.MEASUREMENTS:SM: 7.48"L x 4"W x 0.125"H