Metallics MGRK4SS 5/16x4 Round Washer Head Star Drive Rugged Structural Wood Screws - T-30 305 Stainless Steel RSS™ - Each

That is exactly what the MGRK4SS is for. Metallics states it suits anywhere you would use a traditional lag screw. It is a 5/16 by 4 inch rugged structural wood screw with a round washer head, so the head bears like a lag plus washer, and the star drive lets you drive it with an impact driver instead of a socket wrench. Unlike a lag, no predrilling routine is implied by the design.

They are 305 stainless steel RSS screws, which is a corrosion resistant austenitic stainless rather than a coated carbon steel. That is the material property crews look for on decks, ledgers, railings, and other wet or exterior wood work where a plain or zinc lag would rust out.

Metallics lists the MGRK4SS as Buy American compliant and ARRA compliant, which is what public agency, school, and federally funded procurement usually needs on the submittal. Country of origin is recorded as multiple, so if a project requires a single named origin, confirm the origin on the specific lot you receive.

A T-30 star (Torx style) bit. Metallics specifies the T-30 drive on this 305 stainless RSS screw, so stock T-30 bits before the crew starts. No bit is described as included.

The MGRK4SS ships as a box with a 100 count minimum order. Plan quantities in multiples of 100 rather than by the piece.

No. The head is a round washer head, so the bearing surface is formed into the screw itself. That is one of the practical differences from a lag bolt, where you add a flat washer to keep the hex head from crushing into the wood.

1.94 lbs is the listed product weight, with carton dimensions of 7.25 x 6.75 x 3.25 inches. Useful if you are staging material by the box on a lift or calculating a shipment of multiple cartons.