5/16"-18 x 3 1/2" A307 Grade A Square Head Machine Bolt Low Carbon Steel Zinc Plated

PRODUCT SPECIFICATIONS (Part # 0000-118627)
Fastener Type:	Square Head Machine Bolt
Size Description:	5/16"-18 x 3 1/2"
Diameter/Nominal Size:	5/16"
Length:	3 1/2"
Wrench Size/Across Flats:	0.484-0.500"
Width Across Corners:	0.665-0.707"
Head Height:	0.186-0.220"
Thread Pitch:	18
Thread Direction:	Right
System of Measurement:	Inch
Grade:	A (2)
Material:	Low Carbon Steel
Finish:	Zinc Plated
Head Type:	Square
Drive Type:	External Square
Standards Met:	A307
Average Piece Weight:	0.0800000 lbs.

Square head bolts, or square head machine bolts offer a large bearing area for positive gripping; primarily used nowadays for aesthetic projects that create a rustic look or to match existing fasteners; comes in both fully threaded and partially threaded pitches. Square head bolts are sometimes selected over hex heads because the head will fit neatly in a channel.