5/16" Zinc Plated Steel Pushnut Washers PSHNT-043 (30 pcs.)

Diameter: 5/16"
Material: Steel
Finish: Zinc
Shape: Round
Style: Washer
Type: Push Nut

Box of 30.

Instead of threads a push nut uses flanges facing inward acting as teeth to hold it in place. It can be pushed or lightly tapped into place and requires cutting to remove.