Adhesive Lined Shrink Tubing
Easy waterproof connection
Double-walled, or adhesive-lined, heat shrink tubing is how you make easy waterproof connections. As you heat the tube and it shrinks, it compresses a heat-sensitive adhesive inside the tube to melt into one waterproof seal. This sample set is a good place to start.
12/24/12Ancor Marine Grade Electrical Adhesive Lined Heat Shrink Tubing Kit $12 for a pack of 8