TrussLOK Structural Wood Screw

TrussLOK® is a code-compliant structural wood screw designed for joining multi-ply LVL, LSL and PSL. This fastener was developed with direct input from leaders in the engineered wood market. TrussLOK® is faster, easier and stronger than through-bolts and other structural self-drilling fasteners with similar diameters. It is approved for single-sided installation unlike nails and other screws of similar diameter that need to be installed from both sides. TrussLOK features a hex head drive system and each package contains a free driver bit.

  • No predrilling! Faster and easier than through-bolts
  • Higher side load capacity with fewer fasteners saves time and labor
  • Correct thread length for engineered lumber – No board jacking
  • Prevents gapping or cupping between plies which can occur in nailed applications
  • Winged point, modified thread design and anti-friction coating combine to significantly reduce installation torque

For TrussLOK technical information and fastening patterns, see the Technical Docs section below. For technical documentation of all our structural wood screws, see our Technical Resources page.


TrussLOK Structural Wood Screw for Multi-Ply Engineered Wood Beams

Learn how to fasten multi-ply engineered wood beams using our code-compliant TrussLOK Structural Wood Screw.

  • Sku Selections
  • Installation
  • Technical Docs
  • Purchase FM Products
TrussLOK SKU Selection Guide
3 3/8" 50 pc box FMTSL338-50
250 pc bucket FMTSL338B-250
5" 50 pc box FMTSL005-50
250 pc bucket FMTSL005B-250
6 3/4" 50 pc box FMTSL634-50
250 pc bucket FMTSL634B-250
  • TrussLOK should be installed using a 1⁄2" corded or 18 volt cordless drill.
  • Bring underside of washer-head flush with wood surface. Do not countersink.

For fastener spacing and patterns refer to our technical bulletin (located in the Technical Docs section or our Technical Resources page).

ICC-ES Report, ESR 1078

The ICC-ES Evaluation Report demonstrates to the installer and code official that our LOK fasteners comply with the most current building codes. This report also provides the engineer with critical values needed to design safe installations. Reports from ICC-ES are the most recognized reports used by code officials across the U.S. This document can be shared with code officials, engineers, architects and specifiers who may have questions regarding proper use or code compliance of LOK fasteners.

Technical Bulletins

FastenMaster technical bulletins are abridged versions of our TERs that demonstrate general guidelines and fastening patterns.

TrussLOK Technical Bulletin

This file contains technical information on how to fasten this application in a code-compliant manner

TrussLOK Technical Bulletin - Canadian Version

This file contains technical information on how to fasten this application in a code-compliant manner - Canadian version (both English and French)

DWG Drawings

For use in CAD software

Warranty Information

TrussLOK Guarantee of Performance

This file contains information regarding TrussLOK guarantee of performance

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