Simpson Strong-Bolt 2 Wedge Anchor in 3/8 in. x 7 in. is a high-performance concrete fastener built from Type 304 stainless steel, delivering long-lasting corrosion resistance in demanding service environments. Engineered by Simpson for both cracked and uncracked concrete, this expansion anchor excels in seismic zones, high-wind regions, and applications where structural integrity cannot be compromised. Its dual undercutting embossments on each clip segment allow secondary expansion if a crack intersects the anchor location - keeping the anchor load-capable even when the concrete hole expands. Whether you are securing structural connections in horizontal, vertical, or overhead orientations, this wedge-type anchor provides the confidence of tested, code-listed performance.

Key Features

• Type 304 stainless steel construction - resists corrosion across a wide variety of service environments, including wet, humid, and chemically active conditions
• Code listed for cracked and uncracked concrete - meets building code requirements for both new construction and retrofit applications without needing a separate anchor for each condition
• Dual undercutting embossments on each clip segment enable secondary expansion - significantly increases load-carrying capacity when a crack forms and intersects the anchor hole
• Qualified for static and seismic loading conditions (seismic design categories A through F) - appropriate for use in the most demanding seismic regions in the country
• Chamfered top design - prevents mushrooming during installation, making the anchor easier to drive and keeping the threads clean for the nut
• Suitable for horizontal, vertical, and overhead applications - gives installers flexibility to use a single anchor type across multiple orientations on a jobsite
• Standard ANSI fractional sizing at 3/8 in. diameter - fits standard fixtures and installs with commonly available drill bits and tools, reducing specialty equipment needs
• Tested per ACI 355.2 and AC193 - independently verified performance data supports engineering calculations and code submissions
• Thread length of 5 9/16 in. - provides ample thread engagement for a range of fixture thicknesses and embedment depths

Why This Product

• Designed specifically for seismic and high-wind conditions - if your project falls under seismic design categories A through F, this anchor is qualified for those loading scenarios without requiring special engineering exceptions
• Secondary expansion capability addresses real-world cracking - concrete cracks over time, and the dual embossment design means the anchor continues to carry load after a crack forms, rather than losing holding power
• Type 304 stainless steel is the right material choice for environments where carbon steel would corrode - a direct upgrade from zinc-plated anchors in locations exposed to moisture or corrosive conditions
• Fully assembled and ready to install - the anchor arrives complete, so there is no on-site assembly before driving into the drilled hole, keeping the installation process efficient

Specifications

• Brand: Simpson Strong-Tie
• Diameter: 3/8 in.
• Length: 7 in.
• Thread Length: 5 9/16 in.
• Drill Bit Diameter: 3/8 in.
• Material: Type 304 Stainless Steel
• Finish: Type 304 Stainless Steel
• Anchor Type: Wedge anchor (expansion)

Available Pack Options

• STB2-377004SS: 50 Pk
• STB2-377004SS -4P: 200 Pk

Install With

• Installs with 3/8 in. drill bit and 9/16 in. wrench size

Frequently Asked Questions

Can this anchor be used in cracked concrete?

Yes. The Strong-Bolt 2 is code listed for both cracked and uncracked concrete applications. The dual undercutting embossments on each clip segment enable secondary expansion if a crack forms and intersects the anchor location, significantly increasing the ability of the anchor to carry load even when the hole expands.

What seismic design categories is this anchor qualified for?

This anchor is qualified for static and seismic loading conditions covering seismic design categories A through F - the full range of seismic zones used in building codes. It has been tested per ACI 355.2 and AC193 to support these qualifications.

What drill bit size and wrench size are needed for installation?

Installation requires a 3/8 in. drill bit to bore the hole in the concrete and a 9/16 in. wrench to tighten the nut. These are standard ANSI fractional sizes, so common tools found on most jobsites are sufficient.

Why is Type 304 stainless steel specified for this anchor?

Type 304 stainless steel provides long-lasting corrosion resistance for a wide variety of service environments. It is the appropriate material choice when the anchor location is subject to moisture, humidity, or other conditions that would degrade a standard zinc-plated carbon steel anchor over time.