SAE J429 Grade 8 hex head cap screws are common, high-strength fasteners manufactured from heat-treated medium carbon alloy steel, quenched and tempered. Grade 8 cap screws are available in diameters from 1/4" through 1 1/2" inclusive. Dimensional specifications are governed by ASME B18.2.1. Grade marking consists of 6 radial lines. Inch series fasteners meeting SAE J429 Grade 8 specifications are general use fasteners commonly used in automotive and construction related industries. These fasteners are available in yellow zinc plated finish. Zinc plating sacrifices itself, corroding before the base material, offering added corrosion resistance.