282Pcs Heat Shrink Tubing 3:1 Marine Grade Waterproof Adhesive Lined Black Red. 1/4" Waterproof Heat Shrink Tubing Marine Cable Wrap Adhesive Lined 3:1 Ratio. High Quality Tinned Copper Core-Heat shrinking connector copper core uses tinned copper, which is easier to flatten and grasp the wires, to enhance electrical conductivity.
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