[Upgraded Solid Brass] Includes 300 sets of 1/2' #4 solid brass grommets and washers, rust-proof for outdoor use on fabrics, leather, denim, tarps, canvas & vinyl, etc - ONLY compatible with our hand [Premium Handcraft Essential] Achieve precise holes with hole cutter, then set grommets and washers to the machine for a superior punch finish to elevate craftsmanship beyond standard machines, [Durability] Crafted from sturdy solid brass material, are resistant to corrosion and wear, ensuring a long-lasting finish on your projects. [Specification Dimensions] Inner Diameter(Hole Size After Setting) 1/2' (12 mm), Outer Diameter(Top of Grommet) 7/8' (22 mm), Height 1/4' (6.5 mm). [Widely Used] Versatile and can be applied for banners, tarpaulins, awnings, curtains, signs, posters, large production of clothing and leather manufacture, great choice for repairing fabrics,