Ideal for Making Posters, Tags, Bags, Curtains, Belts, Dresses, Shoes, etc. 1000 Grommets + 1000 Washers #4 ( 1/2") Size Made of Iron with Brass Finish Hole Size After Setting = 1/2"(12mm) Flange Diameter (Top of Grommet)=0.838"(21.3mm) Under Flange Height=0.276"(7mm) Package includes 1000 Grommets and 1000 Washers. As grommet machines use different sizes of dies, please make sure this grommet size fits your machine before purchase. Type Hole Size after Setting Flange Diam. Under Flange Height  #4 1/2"(12mm) 0.838"(21.3mm) 0.276"(7mm)