0I wanted a roof rack to carry the occasional 2x4 or plywood, etc. but didn't want to spend the money required by the after market suppliers.  While in my local big box hardware store I came across the aisle that contained the electrical conduit supplies.  They had an item they called "UniStrut" it's made out of mild steel and looks like a "u" with rolled over lips at the top of the u. They had another item called "top grip nut" that slides in the unistrut channel then turns 90 degrees to lock i