The insulating pipe is designed to be waterproof and sealed to prevent corrosionFeatures:Waterproof When heat is applied, polyolefin tubing reduces in size and adhesive flows inside the insulation. Dual walled tubing ensures waterproof seal and prevents wire corrosionEasy to install Solder and seal process for all your connections. Just use it with heat Guns to seal.Easy identification Color-coded tubing makes it easy to identify the right size of the connector and easily choose the right connector by looking at wire size chart on the box.Durable Made with only the highest quality materials such as PE Plastic, Tin, and Copper to ensure the standard of each connector.Convenient design Allows visual inspection, prevents corrosion, and provided a waterproof seal. Size :White:26x1.7mmRed:40x2.7mmBlue:40x4.5mmYellow:40x6mmColor: Red, Blue, White, Yellow Contains: