C.S. Osborne Black Plain Rim Grommets And Washers. Brass material with dull black finish grommets and washers. You will receive 144 grommets and 144 washers. Made in USA. Size : 2 Diameter of hole : 3/8" 144 washer and grommets per gross Set these grommets with one of the following tools: C.S. Osborne Plain Washer Grommet Setter, C.S. Osborne Grommet Kits or Press-N-Snap Tool. Punch holes before setting grommets with one of the following tools: C.S. Osborne Drive Hole Punch, C.S. Osborne Revolving Hole Punch or Screw Hole Punch.