The Simpson Strong-Bolt 2 1/2 in. x 7 in. Wedge Anchor in Type 316 Stainless Steel is a high-performance wedge-type expansion anchor built for demanding concrete fastening applications where reliability and corrosion resistance are non-negotiable. Engineered with dual undercutting embossments on each clip segment, this anchor delivers secondary expansion should a crack form and intersect the anchor location - significantly increasing its ability to carry load even if the hole expands. Whether you are securing structural connections in seismic zones, high-wind environments, or corrosive service conditions, this Simpson anchor is code listed and tested to perform.

Key Features

• Dual undercutting embossments on each clip segment - enable secondary expansion if a crack intersects the anchor location, maintaining load capacity even as conditions change
• Code listed for cracked and uncracked concrete applications - gives contractors and engineers the documentation needed for inspections and permit-required projects
• Qualified for seismic design categories A through F and static loading - covers the full range of seismic risk categories, making this anchor suitable for the most demanding structural fastening requirements
• Chamfered top design - prevents mushrooming during installation so the anchor seats cleanly and the nut threads properly every time
• Suitable for horizontal, vertical, and overhead applications - provides installation flexibility across a wide range of jobsite orientations without requiring a different product
• Standard ANSI fractional sizing with 1/2 in. drill bit and 3/4 in. wrench compatibility - fits common fixtures and works with standard tools already on the job, reducing setup time and eliminating the need for specialty equipment
• Full Type 316 Stainless Steel construction throughout all components - delivers long-lasting corrosion resistance across a wide variety of service environments, including moisture-prone and chemically exposed settings
• Tested per ACI 355.2 and AC193 - independently verified performance gives specifiers and installers confidence that load ratings meet established industry standards

Why This Product

• Built for worst-case concrete conditions - the dual undercutting embossment design provides secondary expansion when cracks develop at the anchor location, so load transfer is maintained rather than compromised when the unexpected happens
• Full seismic and high-wind qualification from category A through F - this anchor is not simply rated for mild seismic exposure; it is qualified across every seismic design category, making it a dependable choice for projects in the most demanding geographic and structural contexts
• All-316 stainless steel construction on every component - because the anchor body, nut, washer, and clip are all Type 316 Stainless Steel, there are no mixed-metal weak points that could corrode faster than the rest of the assembly in harsh or coastal environments
• Installs with common tools and standard drill sizes - ANSI fractional sizing means no special bits or adapters are needed, keeping installation straightforward and reducing the chance of sizing errors on the job

Specifications

• Model Number: STB2-50700S6F25
• Coating/Material: Type 316 Stainless Steel
• Size: 1/2 in. x 7 in.
• Drill Bit Diameter: 1/2 in.
• Thread Length: 5-5/16 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 25 and Cartons of 100

Approved Applications

• Cracked concrete installations
• Uncracked concrete installations
• Seismic applications requiring code-listed anchoring solutions
• High-wind condition applications
• Corrosive or moisture-prone service environments where stainless steel is required

Frequently Asked Questions

Is the Strong-Bolt 2 STB2-50700S6F25 approved for use in cracked concrete?

Yes. The Strong-Bolt 2 is code listed for both cracked and uncracked concrete applications, making it suitable for a broad range of structural fastening scenarios including those in seismic and high-wind zones.

What makes this anchor perform well when concrete cracks occur at the anchor location?

The Strong-Bolt 2 features dual undercutting embossments on each clip segment that enable secondary expansion should a crack form and intersect the anchor location. This design significantly increases the anchor's ability to carry load even if the hole expands.

Why is Type 316 Stainless Steel used for all components of this anchor?

Type 316 Stainless Steel offers long-lasting corrosion resistance across a wide variety of service environments. All components - including the anchor body, nut, washer, and clip - are made from Type 316 Stainless Steel to ensure uniform performance and resistance to corrosion throughout the entire assembly.

What drill bit size is required to install the STB2-50700S6F25?

A 1/2" diameter drill bit is required to install this anchor, matching the 1/2" anchor diameter for a proper fit in concrete.

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