1.The design that the polyolefin tubing on the outside and the hot melt adhesive on the inside create a durable waterproof seal between the wire and the connector.^ 2.Sealed connectors would prevent corrosion even in the wettest environments.^ 3.The transparent sleeve of butt connectors provides visual inspection. --- You can control the working temperature and heating time.^ 4.Solder and seal-in connectors allow you to use them in hard-to-reach environments or in limited spaces. Since no crimping is required, you just need to position the stripped wires in the solder sleeve and apply heat to complete the connection. An easy one-step connection of wires, insulated and sealed.^ 5.It is widely used in marine, boat, automobile, DIY, etc. the same color connector is the same type of connector, allowing you to easily deflect them and select the correct connector.^