I put never wet on my double blade paddle blades and lower shaft.  The water falls off and does not run down the shaft. I get much less water in the boat. I do not like to feel it so I do not get it on the part my hands touch. It has been on for about 4 hours of paddling and still works well but I do not have a longer test to see how long it will last.    I like it and have put it on my single blade but have not tried it out.