Lateral Extensions used for: Toe in Ankles (Varus) fetlocks Bowed and Offset Knees Bowed HocksOptimal correction requires early application. (Birth to 2 months due to early physis closure.) Medial Extensions used for: Knock Knees (Valgus) Valgus Hocks(Early correction offers better response.) Note: This shoe has little or no effect on toe out rotational deformities. This deformity often appears to be a valgus fetlock which is extremely rare in developing young horses. Reasons for Use: Easy to apply (adjustable) Dramatic results when used early Enhances dynamic stability Relieves stress on young bones Minimizes hoof and joint distortion Caution: remove shoes as recommended to avoid unwarranted pinching effect. We do not recommend reusing the extensions. Inside the cuff there is a felt liner that acts as a release membrane so that when you remove the cuff it does not pull at the hoof wall.