Champion Therma-Kool Compress. Sturdy, gel-filled plastic envelope that is designed for use as a hot or cold compress. Includes a soft outer cover with fastening strap. It stays soft after repeated usage, and is safe for use with children. Hospital proven. Choose Size: (4" x 9" compress) for the ankle, elbow, and knee application; (6" x 10" compress) for the knee and shoulder; (8" x 10" compress) for lower back or shoulder. Use For: Immediate post-injury and recovery phases