Don't try this at home kids (I'm a seasoned legal counsel) but I actually attached them to the SIDES not the tops (didn't have enough slack) . my application). I'm amazed at how well they work, my little freezer slides in and out like it's floating in mid-air. Of course I had to drill a few holes and do some engineering, but it definitely made my life easier, especially now that the freeze season has arrived. (I know, I know, I probably voided my warranty, but Jimmy pops corn, I don't care!) Great product.