Simple Roller (no supports)

I needed a roller to go on the back of a sliding shelf I made, thought it might be useful for other applications. Uses a 608 bearing and a 5/16" x 1 1/2" bolt (M8 x 40mm should work fine). I also used a locking nut, but I don't think it's necessary. I left the mounting holes small because I was mounting with drywall screws. You can drill them out or remix larger.