The Simpson Strong-Bolt 2 Wedge Anchor is a 5/8 in. x 6 in. wedge-type expansion anchor engineered for high-performance structural fastening in the most demanding conditions, including seismic and high-wind applications. Built from zinc-plated carbon steel, it features dual undercutting embossments on each clip segment that enable secondary expansion should a crack form and intersect the anchor location - significantly increasing the anchor's ability to carry load even as the hole expands. Code listed for cracked and uncracked concrete as well as masonry, and tested per ACI355.2 and AC193, the Strong-Bolt 2 delivers the reliability and code-backed performance that contractors and engineers depend on across a wide range of structural fastening applications.

Key Features

• Dual undercutting embossments on each clip segment - enable secondary expansion if a crack intersects the anchor, maintaining load-carrying capacity even as the hole expands and reducing the risk of anchor failure in compromised concrete.
• Code listed for cracked and uncracked concrete and masonry - gives engineers and contractors the documentation they need for inspections and permits across a broad range of substrate types.
• Qualified for seismic design categories A through F and static loading conditions - covers the full spectrum of seismic risk levels, making this anchor a dependable choice for high-seismic zones and high-wind structural connections.
• Suitable for horizontal, vertical, and overhead installations - provides installation flexibility so a single anchor solution works across multiple orientations on a jobsite.
• Chamfered top design - prevents mushrooming during installation, protecting the threads and making nut seating faster and more reliable.
• Tested per ACI355.2 and AC193 - independently verified performance gives specifiers and inspectors confidence that the anchor meets recognized industry testing standards.
• Installs with a 5/8 in. drill bit - matches the anchor diameter exactly, simplifying tool selection and reducing setup time on the job.

Why This Product

• Built for cracked-concrete confidence - unlike basic wedge anchors that lose effectiveness when concrete cracks, the Strong-Bolt 2's secondary expansion mechanism is specifically engineered to maintain holding strength in cracked concrete, making it one of the most reliable choices for concrete anchor applications where structural integrity cannot be compromised.
• Full seismic range coverage in one anchor - qualifying for seismic design categories A through F means this single wedge anchor handles everything from low-seismic-risk residential work to the most demanding high-seismic commercial and industrial structural connections, eliminating the need to source multiple anchor types for different projects.
• Code-listed and independently tested performance - ACI355.2 and AC193 testing, combined with code listing for both cracked and uncracked concrete and masonry, provides the documentation trail that engineers, inspectors, and building officials require, streamlining the approval process on regulated construction projects.
• Fully assembled and ready to install - the anchor ships completely assembled and installs with common tools, reducing on-site preparation time and lowering the chance of misassembly during fastener installation.

Specifications

• Size: 5/8 in. x 6 in.
• Manufacturer Part Number (MPN): STB2-62600F20
• Brand: Simpson Strong-Tie
• Anchor Type: Wedge-Type Expansion Anchor
• Diameter: 5/8 in.
• Length: 6 in.
• Thread Length: 3-15/16 in.
• Material: Carbon Steel
• Coating/Finish: Zinc Plated
• Installation Drill Bit Size: 5/8 in.
• Wrench Size: 15/16 in.
• Packaging: Packs of 20 and Cartons of 80

Approved Applications

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

Frequently Asked Questions

Is the Strong-Bolt 2 suitable 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 on each clip segment enable secondary expansion if a crack forms and intersects the anchor location, significantly increasing the anchor's ability to carry load even as 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 of seismic design categories - making it suitable for high-seismic and high-wind structural applications.

What tools are needed to install the Strong-Bolt 2 wedge anchor?

The Strong-Bolt 2 installs with a 5/8 in. drill bit and requires a 15/16 in. wrench size for tightening. The chamfered top is designed to prevent mushrooming of the anchor during the installation process.

What standards was the Strong-Bolt 2 tested to?

The Strong-Bolt 2 has been tested per ACI355.2 and AC193, ensuring it meets rigorous performance requirements for wedge-type expansion anchors in both static and seismic loading conditions.

Note: Product dimensions and/or thread length may differ from picture. Please refer to the specifications listed above for accurate product details.