I recommend 'Boltlockwashersnut' brand of ducttape. It can be found in the hardware section of your favorite Menard's. Doesn't have the designer look, but does the job cheap. For a more high end look, pick up a can of chrome spray paint and dress up those timbers. My brother and I used a pair of these for many years. For grins we stenciled 'Yakima' on this rails. ;) Use treated 2x4s.