Slide this piece onto your kayak paddle. Then you will be able to have a quick connect for your leash using a carabiner.Using MakerBot software, just scale by 1000% when first added. Print can be done with no support or rafts. I printed mine with 3 shells and 50% infill. I fell that any infill would work well. I also showed how I made a leash for my kayak by taking an old phone charger and some thimble clips. I did have to sand down the inside leash connector so that it would slide onto my paddle with out messing up the rubber on it. This paddle that it was used for had a diameter of 29 mm.