The Simpson Strong-Bolt 2 3/8 in. x 3-1/2 in. Wedge Anchor in Type 316 Stainless Steel is a wedge-type expansion anchor engineered by Simpson for high-performance concrete fastening in some of the most demanding service environments and structural conditions. Dual undercutting embossments on each clip segment enable secondary expansion should a crack form and intersect the anchor location, significantly increasing the ability of this anchor to carry load even as the hole expands - making it a dependable choice for cracked concrete, seismic zones, and high-wind applications alike.

Key Features

• Fabricated from Type 316 stainless steel throughout - delivers long-lasting corrosion resistance in harsh service environments including those exposed to moisture, chemicals, and coastal conditions.
• Code listed for cracked and uncracked concrete applications - gives engineers and installers the confidence to specify this anchor across a broad range of structural conditions without compromise.
• Dual undercutting embossments on each clip segment - allow secondary expansion if a crack intersects the anchor, maintaining load-carrying capacity where standard wedge anchors may fail.
• Qualified for static and seismic loading conditions (seismic design categories A through F) - meets the requirements of the most demanding code-compliant installations, including high-wind and earthquake-prone regions.
• Chamfered top design - prevents mushrooming during installation, making the process cleaner and reducing the risk of installation errors.
• Suitable for horizontal, vertical, and overhead applications - provides versatile placement options for structural and mechanical fastening in concrete.
• Standard ANSI fractional sizing at 3/8 in. diameter - installs with a common 3/8 in. drill bit and 9/16 in. wrench, so no specialty tooling is required.
• Tested per ACI355.2 and AC193 - independently verified performance gives specifiers and contractors confidence in compliance with current building code standards.

Why This Product

• Built for cracked concrete where other anchors fall short - the secondary expansion mechanism provided by the dual undercutting embossments means this anchor continues to perform even when a crack develops at the anchor location, a critical advantage in concrete structures subject to seismic or dynamic loading.
• Type 316 stainless steel construction resists corrosion in environments that compromise standard anchors - ideal for exterior, coastal, or chemically exposed installations where long-term integrity and reduced maintenance are priorities.
• Seismic design category A through F qualification covers the full range of code requirements - contractors and specifiers working on projects in high-seismic or high-wind regions can rely on this anchor without sourcing a separate product for elevated load conditions.
• ANSI fractional sizing means no special tooling or custom fixtures are needed - the 3/8 in. diameter fits standard fixtures and installs with commonly available drill bits and hand tools, reducing setup time and job-site complexity.

Specifications

• Model Number: STB2-37312S6F50
• Coating/Material: Type 316 Stainless Steel
• Size: 3/8 in. x 3-1/2 in.
• Drill Bit Diameter: 3/8 in.
• Thread Length: 2-1/16 in.
• Anchor Body Material: Type 316 Stainless Steel
• Nut Material: Type 316 Stainless Steel
• Washer Material: Type 316 Stainless Steel
• Clip Material: Type 316 Stainless Steel
• Anchor Type: Wedge-Type Expansion Anchor
• Packaging: Packs of 50 and Cartons of 250

Frequently Asked Questions

Is the Strong-Bolt 2 STB2-37312S6F50 suitable for cracked concrete?

Yes. The Strong-Bolt 2 is code listed for both cracked and uncracked concrete applications. Its dual undercutting embossments on each clip segment allow secondary expansion should a crack form and intersect the anchor location, significantly increasing load-carrying capacity even as the hole expands.

Why is Type 316 stainless steel used for this anchor?

Type 316 stainless steel offers long-lasting corrosion resistance for a wide variety of service environments, making it especially well-suited for applications exposed to moisture, chemicals, or coastal conditions where standard carbon steel anchors would be prone to corrosion.

What drill bit diameter is required to install the STB2-37312S6F50?

Installation requires a 3/8" diameter drill bit, which matches the anchor's nominal diameter for a properly sized hole in concrete.

Can this anchor be used in seismic and high-wind conditions?

Yes. The Strong-Bolt 2 wedge anchor is an optimal choice for high-performance applications, including those subject to seismic and high-wind conditions, and is code listed accordingly for qualifying cracked and uncracked concrete installations.

Note: Product dimensions and/or thread length may differ from picture. Please see the item description above for specifications.