DINGYUAN Wire Connectors Kit SPECIFICATIONS: Shrinkage ratio 2:1Dual-walled design tubing: polyolefin tubing on the outside and hot melt adhesive inside Color coded connector tubing Heat activated waterproof adhesiveLow temperature solder sleeve Minimum shrink temperature: 80CMinimum temperature for solder to melt: 118C Why you choose us? Effectively prevent copper layer from rusting and anti-oxidation High quality ensures no exposed wires double wall heat shrink Rugged and Corrosion Resistant enough hot melt adhesive to shrink DINGYUAN Solder Seal Heat Shrink Butt Wire Connectors Waterproof Seal-Dual-Walled tubing ensures waterproof seal and prevents wire corrosion. Hot Melt Adhesive & Solder inside, sealed with Advanced Waterproof Function Fast & Easy Operation-Just strip your wires, insert them into the connector and apply heat.