Surfboard wax has been used for years by paddlers in particular to rub on the paddle shafts to increase grip. However it is also very useful for quick on the water repairs like small cracks, holes or splits.
It can be scraped or rubbed into the area to seal a split (classic plastic boat damage), or softened in the hand and then moulded into a putty like consistency to fill a small hole. It is important to have the correct temperature wax if you are going to soften it in your hand.
An essential item to keep in your buoyancy aid pocket.
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