FlatLOKTM Structural Wood Screws


Reference Series: SDW
FlatLOK is a multi-purpose structural wood screw that can be used for fastening multi-ply SCL, dimensional beams and girder trusses. The low-profile flat head allows for easy attachment of finishing materials such as drywall.

The FlatLOK screw has a shank diameter of 0.227” and is stamped with head mark for easy length identification. The proprietary coating provides protection that exceeds the protection provided by HDG coatings conforming to ASTM A153. FlatLOK may be used for interior and exterior applications and in pressure treated (ACQ) wood.

The FlatLOK wood screw features a TORX® ttap® drive system that maximizes bit fit, reducing the potential for stripping. The stability button allows for maximum penetration into the fastener and a wobble-free drive. A free TORX ttap bit is included in every box.

Materials: Heat-treated carbon steel

Finish: Proprietary coating

Code Reports: View Code Report Table



  • Using an impact driver or high torque 1/2" variable speed drill, bring fastener flush with wood surface. Do not overdrive. No pre-drilling required when properly installed.
  • Screws may be installed through metal truss connector plates as approved by the Truss Designer. (Pre-drilling required through the plate using a maximum 5/32” bit.)
  • Engineered Wood Beams: Refer to Multi-ply Engineered Wood Beams technical bulletin Click here and engineered wood manufacturer's technical document for complete load and engineering requirements.
  • For applications other than those listed above, refer to Design Values technical bulletin Click here for English, Click here for French for design information to determine a proper connection solution. Consult a design professional as needed.

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