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Construction Lag Screw

Structural • Corrosion-Resistant


Construction Lag Screw

Structural • Corrosion-Resistant

Heat-treated hardened steel
#14 x 1ʺ to #17 x 16ʺ
Round Washer Head
Star Drive

Compatible with treated lumber, but areas within one mile of saltwater, near swimming pools, exposure to corrosive chemicals, or other areas where corrosion is more likely to occur, such as livestock confinement, use the proper size, grade and type of Big Timber Stainless Steel Fasteners. Stainless available as SCTX.

Mountain Tested Fasteners

Big Timber CTX: Structural Lag Screw

Common Uses Include

• Log Construction
• Timber Frames
• Laminated Beams
• Girders
• Ledger Boards
• Stair Rails
• Deck Posts
• Fencing
• SIP Panels
• Pole Barns


Benefits and Features:

• Heat-treated hardened steel for high tensile strength and high shear strength
• Triple Layer ACQ Compatible Bronze Coating for Exterior or Interior use
• Wax coating enhances performance, reducing the torque for a smoother drive
• Deep Six-Lobe Star Drive Recess reduces cam-out end load. Handles twice the torque as Phillips or Square Drive while extending the life of the bit
• Built-in washer head for increased pull through strength
• Under-head cutting nibs to aid in self countersinking
• Aggressive knurl enlarges hole to reduce splitting and drag to help draw lumber together
• V-Cut notches on threads to cut fibers for easier insertion at lower torque
• Type 17 tip for faster precise starts which eliminate “walking”
and provides easier insertion without pre-drilling
• Aggressive Thread for great withdrawal strength
• Structural Lag Screw backed by certified independent testing (TER 1907-01) (Acceptable alternative to galvanized lag screws)
• International Building Code and International Residential Code Compliant

CTX Product Options

0.531" / T251" to 6"930 lbf (Shear 725 lbf)
0.620" / T302" to 6"1,475 lbf (Shear 1,020 lbf)
0.675" / T404" to 16"1,850 lbf (Shear 1,240 lbf)
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