Dual wall heat-shrink tubing will shrink down to 1/3 of its original size after heat is applied. It is optimal for use over wire terminations or areas where cable insulation is exposed. When heat is applied, adhesive melts inside the tube, providing hermetic sealing with waterproof protection and a great tensile strength with long-lasting insulation.
https://selterm.com/products/h....eat-shrink-tubing-ki

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