5 different sizes for your interest: The binding screws are 5 lengths: 6 mm, 10 mm, 12 mm, 15mm and 18mm, all the chicago fixing screws have a diameter of 5 mm which adapts to most objects high quality: Chicago screws are made of quality carbon steel, plated with silver nickel, robust and anti-rust, easy to bind, install and remove, these chicago nest can be used repeatedly with a good sealing Wide application: Screw rivets are particularly suitable for leather craft decoration, binding, document, book, album, DIY crafts, etc. Easy to install: Just use a drill to make a 5 mm diameter hole, and install the 2 pieces on each side Practical Storage: We offer beautiful plastic storage boxes. So, you do not have to fear losing some rivet screws, so you can use them again 80pcs 5 metal sizes binding screws are made of carbon steel, which is solid and durable, with nickelized surface. Kit 5 sizes head screws is ideal for leather, crafts decoration, decorate a document, book, photo album, binding, scrapbooking and other Diy Crafts. Features: 1.Fabricated in quality carbon steel material, silver, robust and anti-rust nickel plated. 2.Reuse: Easy to remove, install and remove; Can use repeatedly. 3.Vis link: 5 assorted sizes, 20 pieces for each size, 100 sets binding screws in total. 4.Ideal for the decoration of leather crafts, binding, document, book, photo album, scrap booking, do-it-yourself , etc. 5. Organized by size in a seamless storage case for quick access and protection. Specification Product name: Chicago screw MATERIAU: Chicago carbon steel Color: Silver Dimension: 5 6mm / 5 10mm / 5 12mm / 5 15mm / 5 18mm Weight: 240g Quantity: 80 The package includes: 16 Chicago screw games (5 x 6 mm) 16 Chicago screw games (5 x 10 mm) 16 Chicago screw games (5 x 12 mm) 16 Chicago screw games (5 x 15 mm) 16 Chicago screw games (5 x 18 mm) 1 x Seamless storage box