[Metal Grommet Size] --- Inside diameter: 5 MM (0.2 Inch), outside diameter: 9 MM (0.32 Inch),barrel length is 3.6 mm (0.14 inch) [Wide Usage] --- The easy-to- grommet kit is suitable for , clothing, shoelaces, projects, tarps, awnings, and leather crafts and adding ornament to your crafts etc. [Easy ] --- All 400 grommets sets and can be put in box with removable baffle to separate these compartments, which is convenient to find the corresponding components The structure is firm.Rustproof durable, performance is good, Color does not off. Installation steps: 1.Making a hole with a punch tool. 2.Put the back of eyelet through a hole from a front of clothes and a washer on the back of eyelet from a back of clothes. 3.Face eyelet to the and wear on the . 4.Push the install rod on washer and hammer the grommet We 't recommend to these grommets for thick fabric (such as wool blankets). the thickness of leather does not exceed 6 . Lightweight fabrics,mesh ,knitted fabrics, fabrics and fabrics with wear on the surface should be lined on the back to prevent from breaking and tearing the fabric Note: Please keep from children to avoid choking. Color: silver + black + green bronze + gold material: metal Package Contents: 400 * Grommets (4 colors and 100 sets each color ) 3 * 1 * box Only the above package content, other products are not included. Note: Light and different displays may the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.