These u shaped rollers enable you to slide your boat onto the roof, making loading easier than pie. And when you add mako saddles securing your boat is easier than pie, tarts, donuts, cupcakes, or pretty much any form of pastry. U shaped rollers fit many hull shapes try. Dynaflex rollers pivot for convenient loading angles. Boats roll on and off effortlessly Heavy duty straps with padded buckles included. Includes bowstern tie down straps to complete kayak stability. Combines with mako saddles for the ultimate combination of easy loading and boat security.