The HellermannTyton 321-50450 Heat Shrink Tubing and Sleeves is a heat shrinkable tubing product with a 3.5:1 thick wall adhesive lined length of 1m and a 45/12 black profile. It is designed for covering electrical connections, soldering joints, or shielding cables from abrasion, moisture, and other environmental hazards. It is made of a flexible elastomeric material that shrinks when exposed to heat, forming a tight fit and providing a smooth, weather-tight seal. The connector also provides excellent electrical insulation, strain relief, and protection against vibrating wires from mechanical stresses. The shrink ratio of the tubing is 3.5:1 meaning that the diameter of the tubing will shrink to one-third of its original size when subjected to heat. The product is UL recognized and CSA certified for excellent electrical insulation.