Pin Diameter: 7.8mm; Material: Plastic; Color: Transparent Used to support and lock in 3/4 inch thick shelves; Note: Please confirm that the shelf thickness is less than 20mm before purchase. Self-Locking Shelf Support Pegs - Easy to install, make the shelves securely stay in place you put them Easy to release - Just press the spring loaded clip, and then you can take down the shelves For a tight fit effect, the holes diameter should be equal to or slightly smaller than the pin diameter (slightly less than or equal to 5mm); Please make sure the size you need before you buy it Pin Diameter: 7.8mm Fit hole diameter: 7.5mm Material: Plastic Color: Transparent Clear plastic exterior looks great Used to support and lock in 3/4 inch thick shelves Note: Please confirm that the shelf thickness is less than 20mm before purchase For a tight fit effect, the holes diameter should be equal to or slightly smaller than the pin diameter (slightly less than or equal to 5mm) Self-Locking Shelf Support Pegs - Easy to install, make the shelves securely stay in place you put them Easy to release - Just press the spring loaded clip, and then you can take down the shelves Widely used in cabinets, wardrobe, closet, bookshelf, shoebox, and racks Easy to Use - Just install or uninstall it by hand, good choice for DIY Note: Small parts, please stay away from your baby and children Package included: 20 x Plastic Locking Shelf Pins How to use 1. Use an electric drill to punch hole, please use the 7.8mm drill bit. 2. Put the shelf pin in the hole. Warm note: If the hole diameter is bigger than shelf pin diameter, you can wrap a circle around it with scotch tape, and then put the shelf pin in the hole 3. Place the baffle on the shelf pin.