This large set is particularly suitable for DIY enthusiasts, craftsmen, field service, service workshops, electronics professionals, and laboratory supplies. The inner hot melt adhesive ensures a waterproof seal when properly overlapped. It is ideal for repairing or connecting cables and wires (lawn mower cables, signal cables, etc.), service, manufacturing, or hobbies. The application is very simple: strip the cables and insert them from both sides until the stripped ends overlap. Crimp with a crimping tool and then activate the heat shrink tubing within the appropriate temperature range - best done with a heat gun. Waterproof, UL, REACH, and RoHS compliant. Special feature: includes heat shrink tubing.