9/16"-18 x 2-1/2" Zinc Plated Grade 8 Steel Fine Thread Hex Cap Screws

Diameter: 9/16"
Length: 2-1/2"
Material: Steel
Finish: Yellow Zinc
Head Style: Hex (13/16" Wrench)
Thread Size: 18 (Fine)
Thread Length: 1-3/8"
Hardness: Grade 8
Type: Cap Screw

Box of 6.

A hex cap screw has a hexagonal head, designed to be driven by a wrench.