I bought this to use as a slide for a keyboard tray. I have them installed flat on the bottom of the shelf I used and then the other side attached to the desk (the desk has 3 levels and I have the shelf and slides attached to the bottom one. I had done this once already with a regular set of slides, and I broke those when leaning on the shelf one day. I have no worries about these slides doing that. I lean on the shelf every day now, and I'm certain the shelf itself will break before the slides do. Great product.