The Simpson Strong-Bolt 2 1/2 in. x 7 in. Wedge Anchor is a wedge-type expansion anchor engineered by Simpson for high-performance structural connections in concrete and masonry. Built from zinc-plated carbon steel, it is purpose-built to maintain reliable holding power under static loads, seismic events, and high-wind conditions alike. Dual undercutting embossments on each clip segment enable secondary expansion should a crack form and intersect the anchor location, giving this anchor the ability to continue carrying load even if the hole expands - a critical advantage in cracked concrete applications.

Key Features

• Code listed for cracked and uncracked concrete, and masonry applications - gives engineers and contractors the documentation needed to use this anchor confidently across a wide range of structural substrates without additional field verification.
• Dual undercutting embossments on each clip segment - enable secondary expansion if a crack intersects the anchor location, maintaining load-carrying capacity when conditions change and reducing the risk of anchor failure in compromised concrete.
• Qualified for static and seismic loading conditions, seismic design categories A through F - covers the full spectrum of seismic zones, making this anchor a dependable choice for projects in the most demanding regions without requiring a product substitution.
• Chamfered top designed to prevent mushrooming during installation - protects the fastener during driving so the nut seats cleanly every time, reducing installation errors and rework on the job site.
• Suitable for horizontal, vertical, and overhead applications - offers flexibility across different installation orientations, eliminating the need to source multiple anchor types for a single project.
• Tested per ACI355.2 and AC193 - independently verified performance data gives specifiers and inspectors confidence that the anchor meets recognized industry standards for expansion anchor evaluation.
• Installs with a 1/2 in. drill bit and 3/4 in. wrench - straightforward tooling requirements mean no specialty equipment is needed, keeping installation simple and efficient in the field.
• Made from zinc-plated carbon steel - provides a corrosion-resistant finish suited to general construction environments where exposure to moisture is a routine concern.

Why This Product

• Performs where ordinary anchors fall short - the dual undercutting embossment design actively responds to concrete cracking by enabling secondary expansion, so the anchor continues to carry load even after the substrate is compromised - a feature that matters most in seismic zones and aging structures.
• Full seismic code coverage in a single SKU - qualification across seismic design categories A through F, combined with code listing for both cracked and uncracked concrete and masonry, means this wedge anchor can satisfy a broad set of project specifications without requiring multiple product approvals.
• Engineered for all installation orientations - approval for horizontal, vertical, and overhead use means contractors can rely on one anchor solution throughout a project rather than switching products based on anchor position, simplifying procurement and field execution.
• Backed by recognized testing standards - evaluation under ACI355.2 and AC193 provides the documented performance data that engineers, inspectors, and code officials need to approve the anchor on regulated commercial and residential projects.

Specifications

• Size: 1/2 in. x 7 in.
• MPN: STB2-50700F25
• Brand: Simpson Strong-Tie
• Material: Carbon Steel
• Coating / Finish: Zinc Plated
• Anchor Diameter: 1/2 in.
• Anchor Length: 7 in.
• Thread Length: 5-5/16 in.
• Installation Drill Bit: 1/2 in.
• Wrench Size: 3/4 in.
• Packaging: Packs of 25 and Cartons of 100

Approved Applications

• Cracked concrete
• Uncracked concrete
• Masonry
• Horizontal installations
• Vertical installations
• Overhead installations
• Seismic design categories A through F
• High-wind structural connections

Frequently Asked Questions

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

Yes. The Strong-Bolt 2 is code listed for both cracked and uncracked concrete, as well as masonry applications. Its dual undercutting embossments enable secondary expansion if a crack forms and intersects the anchor location, maintaining load-carrying capacity even when the hole expands.

What seismic design categories is the Strong-Bolt 2 qualified for?

The Strong-Bolt 2 is qualified for static and seismic loading conditions covering seismic design categories A through F - the full range - making it suitable for projects in the most demanding seismic zones.

What tools are needed to install the STB2-50700F25?

Installation requires a 1/2 in. drill bit to bore the hole and a 3/4 in. wrench to tighten the nut. The chamfered top of the anchor is designed to prevent mushrooming during the installation process.

What testing standards has the Strong-Bolt 2 been evaluated under?

The Strong-Bolt 2 has been tested per ACI355.2 and AC193, the industry-recognized standards for mechanical anchors in concrete, ensuring its performance ratings are backed by rigorous third-party evaluation protocols.

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