Our Knee Boot has a neoprene exterior lined with state-of-the-art fabric which contains polyester thread embedded with a fine ceramic powder. Designed to reflect the horse's own body-warmth, it creates a soothing far infrared thermal warmth, which can help alleviate pain associated with inflamed muscles, ligaments, tendons and joints. Used for both injury prevention as well as injury recovery.Relieve and Heal Injured Muscles, Joints, and Tendons with our Contoured Horse Knee Boots Our Knee Boots are ideal for injury recovery or prevention in the tough to wrap knee area. Consisting of a neoprene exterior, we infused the interior of the boot with our state-of-the-art Welltex fabric, which contains ceramic powder. The ceramic reflects your horses natural body warmth and creates a soothing far infrared thermal warmth. Warmth therapy is a well-recognized method used to help relieve and heal injured muscles, joints, and tendons. Contoured to the shape of the knee, the boot fastens with hook & loop fastener straps allowing you to adjust the fit. When using these boots it helps to use standing wraps to prevent them from sliding down. Sizes: Top Circum.Bottom Circum.Knee at widest pointSmall111012Medium121113Large131213XLarge141314Typically Arabian sized horses take a Small, Quarter horses a Medium, and Warm Bloods a Large. Care: Machine washable up to 86F or 30C. Use normal detergents that do not contain bleach or fabric softeners. Air dry only, do not tumble dry. Back on Track products are not to be compared with magnetic therapy. The effectiveness of Back on Tracks thermal warmth therapy has been established by medical science.