High-quality material: The grommet is made of high-quality copper-nickel material, with electroplated surface, high corrosion resistance, shiny appearance, and not easy to oxidize. Ease to use: grommet kits make installation easy. First punch a hole in the tarpaulin (fabric) using the punch tool, then take out the eyelet set and finally attach the eyelet set with the included tool. When punching holes, please put rubber pads or wooden boards to prevent the puncher from blistering. Versatile use: grommet kits are suitable for canvas, tarpaulins, tents , curtains, backpacks, leather crafts, repair and decoration. (Material less than 1mm thick). Eyelet Kit: Includes 100pcs eyelet kit (with 100pcs eyelet and gasket, individually packed in a PE saen), one punch tool and a set of tools, all in a damage-free plastic box. Dimensions: inside diameter: 12 mm (1/2") and outside diameter: 21 mm (5/6 "). Bring a plastic storage box, approx. 6.9 x 3.9 x 1.3 inch / 14 x 8 x 3.3cm.