SPAX® PowerLags® T-Star Washer Head Wood Lag Screws

Choose SPAX® PowerLags® T-Star Washer Head Wood Lag Screws. The low-profile, large diameter head design provides outstanding clamping force and improved aesthetics. Deep T-Star drive offers excellent bit engagement without requiring a “special” driver bit. Available in 1/4", 5/16”, and 3/8” diameters, and in lengths up to 10”. Buy SPAX T-Star Washer Head PowerLags and wood lag screws with HCR® high corrosion-resistant coating in bulk pails or in job-friendly package quantities (hex driver included) from wholesalers, dealers, and specialty distributors or retail hardware and home improvement stores near you.

Base Part No.: 358182() or 458182()  


SPAX PowerLags require no pre-drilling and drive faster and easier than conventional lags and other structural lag screws. We offer the largest selection of code-recognized structural wood-to-wood fasteners in the industry. Featuring SPAX patented thread technology and HCR high corrosion resistant coating, our T-Star washer head and PowerLags collection can be used for interior or exterior applications, including treated lumber.

  • Code listings ICC-ES ESR-1782
  • DrJ Technical Evaluation Reports (TER No. 1711-01; Deck Ledger Attachment and TER No. 1802-03; Multi-ply; LVL Beams and Girder Truss Applications)
  • Grade 5 durability
  • No pre-drilling required (1/4" and 5/16")
  • Patented thread serrations require up to 40% less driving torque to increase installation speed while helping prevent cracking in logs
  • Built-on washer head designs eliminate the need and extra cost of a separate washer
  • Fastener length stamp on the head provides convenient identification without measuring and aids on-site inspections

Choose SPAX PowerLags structural wood to wood screws with built-on washer design in a variety of screw styles, including Hex head, T-Star, and multiple coating options. Request a sample pack of SPAX PowerLags today and build strong connections on the job site. Need something stronger? Shop our PowerLags collection designed for timber frame and log home construction.

For CAD documents, please see Technical Documents.

SizeDrive/Bit SizeThreadAvailable Pkg. Options
Sm. PlasticLg. Plastic1 lb. Box3 lb. Box5 lb. BoxPer PieceContractor PackBulk PailProject PAX
1/4" x 2-1/2"T-30Partial1+5050012
1/4" x 3"T-30Partial1+5050012
1/4" x 3-1/2"T-30Partial1+5050012
1/4" x 4"T-30Partial1+5050012
1/4" x 4-1/2"T-30Partial1+5050012
1/4" x 5"T-30Partial1+5050012
1/4" x 6"T-30Partial1+5050012
5/16" x 3"T-40Partial1+5025012
5/16" x 3-1/2"T-40Partial1+5025012
5/16" x 4"T-40Partial1+5025012
5/16" x 4-1/2"T-40Partial1+5025012
5/16" x 5"T-40Partial1+5025012
5/16" x 6"T-40Partial1+5025012
5/16" x 6-3/4"T-40Partial50250
5/16" x 8"T-40Partial1+5015012
5/16" x 10"T-40Partial1+5015012
5/16" x 12"T-40Partial1+50150
3/8" x 5"T-50Partial1+2515012
3/8" x 6"T-50Partial1+2515012
3/8" x 8"T-50Partial1+150
3/8" x 10"T-50Partial1+150
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