Grade 5 Zinc Steel Hex Bolts 5/8"-18 x 8.00" Length

Head Width 15/16", Head Height 25/64". Partially Threaded. Thread Length 1-3/4" to 2-1/4". ASME B18.2.1, SAE J429, Class 2A. Suitable for fastening most machinery and equipment. Zinc plated steel screws resist corrosion in wet environments. Length is measured from under the head.