Washer Head, Stainless Steel Self-Tapping Wood Screw
  • Code Approval
  • ICC, ETA
  • Connection Type
  • Wood/Wood
  • Applications
  • Timber Framing, Log Home Building,
    Mass & Heavy Timber Construction

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Washer Head

Ring Thread Tip

Suitable in Wet Service Conditions


Product Description

Product Description

The A2 Stainless Steel SK are high corrosion resistant structural fasteners suitable for use in wet service conditions & corrosive environments. These ICC-ESR approved fasteners are designed for high-performance outdoor steel to wood applications. They offer a precise setting without the need for pre-drilling [may be recommended for long models].

Made from chromium-nickel austenitic stainless steel (corrosion resistant) with low carbon content and copper addition. Considered to be equivalent to 304 stainless steel.


Diameters1/4″ (6 mm)5/16″ (8 mm)
Lengths3-1/8” (80 mm)  to  14-1/4” (360 mm)
  • Washer head fastener with the highest head pull-through capacity
  • 304 stainless steel equivalents
  • Suitable in corrosive environments
  • Suitable for use in wet service conditions
  • Aggressive ring thread tip providing the fastest fastener wood bite & installation
  • Installed with AW Bits




SpecificationASSY A2 SKThread LengthDrive BitPackaging Qty.
# ItemMaterialHead
A2SK0680Stainless SteelWasher Head1/4" x 3-1/8"6 x 802"50AW 30100
A2SK0690Stainless SteelWasher Head1/4" x 3-1/2"6 x 902"50AW 30100
A2SK06100Stainless SteelWasher Head1/4" x 4"6 x 1002 3/8"60AW 30100
A2SK06120Stainless SteelWasher Head1/4" x 4-3/4"6 x 1202 3/4"70AW 30100
A2SK06140Stainless SteelWasher Head1/4" x 5-1/2"6 x 1402 3/4"70AW 30100
A2SK0880Stainless SteelWasher Head5/16" x 3-1/8"8 x 802"50AW 4050
A2SK08100Stainless SteelWasher Head5/16" x 4"8 x 1002"50AW 4050
A2SK08120Stainless SteelWasher Head5/16" x 4-3/4"8 x 1203 1/8"80AW 4050
A2SK08140Stainless SteelWasher Head5/16" x 5-1/2"8 x 1403 1/8"80AW 4050
A2SK08160Stainless SteelWasher Head5/16" x 6-1/4"8 x 1603 1/8"80AW 4050
A2SK08180Stainless SteelWasher Head5/16" x 7-1/8"8 x 1803 1/8"80AW 4050
A2SK08200Stainless SteelWasher Head5/16" x 7-7/8"8 x 2003 1/8"80AW 4050
A2SK08220Stainless SteelWasher Head5/16" x 8-5/8"8 x 2203 1/8"80AW 4050
A2SK08260Stainless SteelWasher Head5/16" x 10-1/4"8 x 2604"100AW 4050
A2SK08300Stainless SteelWasher Head5/16" x 11-7/8"8 x 3004"100AW 4050
A2SK08360Stainless SteelWasher Head5/16" x 14-1/4"8 x 3604"100AW 4050
CAD Drawings

CAD Drawings

ProductASSY A2 SK DiameterFile Extension
ASSY A2 SK1/4"6
ASSY A2 SK5/16"8
Design Guides

Design Guides

Structural Screw Catalog

A catalog with all information on our ICC & CCMC code-approved fasteners, including dimensions, references & design properties.

Structural Screw Connection Design Guide

Companion to the Structural Screws Catalog, it provides easy-to-read tables for the most common mass timber connections with design values & installation instructions.

Code Approvals

Code Approvals

ICC Code Approval ESR-3179 for Partially Threaded Fasteners - 2022 Edition (October)

ISO 50001 Certification for ASSY Fasteners

LA Research Report (LARR): RR 26073

Installation Instructions

Installation Instructions

Structural Fasteners Installation Guide

The structural fasteners installation guide is a practical document designed to simplify the installation process of ASSY self-tapping screws.

White Papers

White Papers

Supplementary Considerations for the Conventional Yield Model

Screw Buckling Values for Compression Perpendicular to Grain Reinforcement

Withdrawal Resistances of ASSY Screws at Various Angles to the Grain

Timber Moisture Content Changes and Associated Stress Predictions on Structural Wood Screws

Substitution of Lag Screws with Wood Screws

Technical Blogs

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