The HellermannTyton 450-20001 Heat Shrink Tubing and Sleeves Heat Shrinkable Cable Repair Sleeve 43/10 is a cable repair sleeve that is designed to be used in various applications. This 50cm black sleeve is made of polyolefin heat shrink material, which shrinks upon application of heat. It is designed to insulate and protect splices, joints, broken or dented cables, and terminations. Once applied, it provides environmental protection against water, dust, and other contaminants. Additionally, the sleeve provides flexibility and strain relief, which ensure the electrical connections remain securely in place.