The Fold Baseball Finger Splint – Brace for Jammed & Injured Fingers is made with foam lined aluminum. The end of the finger splint wraps over the tip of the finger for extra comfort and protection. There are two bendable aluminum locks that go over and around the finger to further stabilize and immobilize the finger. Size Guide Size Measurements Small 3.5” Medium 4” Large 5” Application Instructions Slip the injured finger into the finger splint so the long side of the finger splint is on the bottom of the finger. Gently push the bendable aluminum locks around the finger until the finger is secure and immobilized. Adjust finger splint for desired fit, support, and comfort.