This quantity of boards will cover up to sq ft

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The ideal fastener for wood-to-wood applications, the HeadLOK Heavy Duty Flathead Fastener by FastenMaster. The unique design gives the HeadLOK screws a higher shear strength than regular 3/8 inch lag screws, eliminating the need to pre-drill, and featuring a non-countersinking head. Crafted from 1022 Carbon Steel Grade with a corrosion resistant coating, HeadLOK screws will help you save time and money on projects such as deck frames, cabinetry, fences, and more. ACQ-rated for use with pressure treated lumber, the HeadLOK screws are not designed to be used within 1000 feet of salt water.

HeadLOK Screws by FastenMaster feature a wafer-style head with a bit engaging Spider drive.

They are available in the lengths of 2-7/8 inches, 4-1/2 inches, and 6 inches; and in packs of 12, 50, 250, and 500 screws to accommodate the project you need.

Note: Not all lengths are available in all pack quantities.
DecksDirect # 5535

Installation Instructions (450 KB) 

ICC-ES Evaluation Report (281 KB) 

Technical Evaluation Report (487 KB) 

Color Clear

Drive TypeSpider drive
Head TypeWafer head
Screw Length2-7/8 in, 4-1/2 in, and 6 in
Screw Size5/16 in


Material Type1022 Carbon Steel Grade with a proprietary corrosion resistant coating
Pack Size

12 pack, 50 pack, 250 pack, and 500 pack
Note: Not all lengths are available in all pack quantities.

Coverage Estimaten/a
Included Accessories2 in spider drive bit
WarrantyHeadLOK Guarantee of Performance
OtherACQ approved
Not designed for use within 1000 ft of salt water
Made in the U.S.A.
Questions & Answers