Heat Shrink Tubing. To keep your boat running smoothly and efficiently all season long, we provide a wide range of boating accessories. Browse from the wide range of products and choose the right boat accessories depending on your needs, preferences and budget.. Features Cross Linked polyolefin tubing is much stronger than PVC tubing and will not burn like PVC; Heat activated adhesive lining provides impervious seal to salt water; Highest shrink ratio – shrinks to 1/3 original size; Operating temperature range of -40C to 110C; Shrinks at 257F / 125C; Specifications Color: Red; Size: 0.75 x 3 in.; .