C.S. Osborne Brass Plain Rim Grommets And Washers. Brass material with brass finish grommets and washers. You will receive 144 grommets and 144 washers. Made in USA. Size : 0 Diameter of hole : 1/4" 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.