The item is a set of 50pcs butt wire crimp connectors terminals, which is made of copper, PVC and tinplate, and it features dual-walled design with polyolefin tubing in outside and hot melt adhesive in inside. They allows visual inspection, , and a waterproof seal. Features - ColorAssorted Color - Material: Copper, PVC, Tinplate - Solder are ideally suited to cable to extend using a heat (with a little practice goes a lighter on the go). - Simply the connector on the stripped cable pull and short warm up until the solder liquefies. - The color marking liquefied well, characterized the whole waterproof is closed. - Once the machined body is cooled, you can strain the cable mechanically. - Easy connection of wires, soldered, insulated and sealed can be ideal. - use in marine and automobile applications Polyolefin tubing in outside and hot - melt adhesive in inside Solder and seal and with advanced waterproof function - Polyolefin heat shrink butt connectors improved pullout strength, provides seal, strain relief, cable check, and insulation - Package Included: 10x white: diameter 1.5mm, for section 0.3 - 0.5 mm² 20x red: diameter 3mm, for section 0.5-1.0 mm² 15x blue: diameter 5mm, for .0-2.5 mm² 5x yellow: diameter 6mm, for - .0-6.0 mm² Package list: 50 * 4 Sizes Waterproof Heat Shrink Tube Terminal Connectors