SPAX® PowerLags® offer an unparalleled level of fastening efficiency, reliability and value for structural wood assemblies and heavy carpentry. Available in two head styles, four diameters, lengths up to 12”, and coating systems that include use in treated lumber, you can be sure you’ll have the right fastener for the application. PowerLags’ patented thread technology requires no pre-drilling and makes installation faster and easier than conventional lags and other structural screws, with connections that are building code compliant. The T-STAR washer head provides a low profile head and eliminates the need for a separate washer. SPAX 5/16” PowerLags have been tested for use in the attachment of deck ledger boards to the building structure to provide prescriptive solutions that are equivalent to the International Residential Code provisions for deck ledger attachment. When installed per DrJ Technical Bulletin No. 1711-01, SPAX 5/16” PowerLags can be used in place of ½” lag screws.