Marine grade butt connectors make quick work of joining wires; and unlike their automotive counterparts they are able to stand up to the harsh marine environment. These heat shrink connectors offer a watertight seal. A heat activated adhesive built into the sleeve of the heat shrink tubing seals the wires from the harsh marine environment and provides vibration and strain relief. The barrels are designed to tightly grip the wire with minimal effort. Wire specific sizing assures a strong connection. Spend less time working on your boat and more time out on the water.