5/16" x 5/8" x 1/4" x 1/16" Black Rubber Grommets

Diameter: 5/16"
Diameter 2: 5/8"
Thickness: 1/4"
Material: Rubber
Finish: Black
Type: Grommet
Groove: 1/16"
GrooveDiameter: 7/16"
Groove: x 1/16"

Box of 20.

Grommets and eyelets are metal, plastic, or rubber rings that are inserted into a hole made through another material. They may be used to reinforce the hole, to shield something from the sharp edges of the hole, or both.