The Simpson Strong-Tie ATRM 1-1/8 in. x 48 in. All-Thread Rod, Grade 55 is a fully threaded steel rod engineered as a tension transfer element for structural systems designed to resist seismic and wind forces. Acting as a continuous and reliable load path from roof to foundation, this all-thread rod is a core component in continuous rod tiedown systems for shearwall overturning restraint, uplift restraint systems for roofs, and can also be used as an adhesive anchor rod in a range of structural applications.

Key Features

• Precut 48 in. length - ready to install without field cutting, saving time and reducing material waste on the job site.
• Grade 55 specification (ASTM A36; Fy = 55 ksi and Fu = 75 ksi) - delivers verified yield and tensile strength for dependable performance in demanding seismic and wind-load applications.
• UNC Class 2A thread specification - ensures consistent thread fit and compatibility with standard threaded hardware used in continuous rod tiedown and uplift restraint systems.
• 1-1/8 in. rod diameter - provides the cross-sectional capacity required for heavy-duty structural connections from roof to foundation.
• Uncoated black steel finish - suited for interior structural installations where a coating is not required, keeping material costs straightforward.
• Made in the United States - manufactured domestically to support consistent quality standards for structural applications.

Why This Product

• Designed specifically for continuous rod tiedown systems, this all-thread rod provides a reliable, uninterrupted load path from roof to foundation - addressing one of the most critical structural requirements in seismic and high-wind construction zones.
• Its Grade 55 rating (ASTM A36; Fy = 55 ksi and Fu = 75 ksi) meets recognized structural specifications, giving engineers and inspectors a verifiable, code-supportable material standard.
• The fully threaded design runs end to end, making it versatile across multiple applications - shearwall overturning restraint, roof uplift restraint, and adhesive anchor rod use - without requiring a special-order configuration.
• Precut to 48 in. and ready to use out of the package, this rod reduces installation steps and helps keep structural framing projects on schedule.

Specifications

• Brand: Simpson Strong-Tie
• MPN: ATRM9-4
• Product Class: Threaded Rod
• Rod Diameter: 1-1/8 in.
• Rod Length: 48 in.
• Grade: Grade 55
• Thread Specification: UNC Class 2A
• Material Standard: ASTM A36; Fy = 55 ksi and Fu = 75 ksi
• Material: Uncoated Steel
• Finish: Uncoated Steel
• Color: Black
• Quantity: 1
• Country of Origin: United States
• Prop 65: No

Approved Applications

• Continuous rod tiedown systems for shearwall overturning restraint
• Uplift restraint systems for roof applications
• Adhesive anchor rod applications
• Structural systems designed to resist seismic forces
• Structural systems designed to resist wind forces

Frequently Asked Questions

What structural systems is this all-thread rod designed to work with?

The ATRM9-4 is designed for use in structural systems that resist seismic and wind forces. It functions as a tension transfer element in continuous rod tiedown systems for shearwall overturning restraint, in uplift restraint systems for roofs, and can also be used as an adhesive anchor rod in other structural applications.

What material standard does this threaded rod meet?

This rod meets Grade 55 specifications and conforms to ASTM A36 with a minimum yield strength of Fy = 55 ksi and a minimum tensile strength of Fu = 75 ksi. The thread form is UNC Class 2A, which ensures compatibility with standard structural threaded hardware.

Is this rod fully threaded along its entire length?

Yes. The ATRM is a fully threaded rod - also referred to as an all-thread rod - meaning threads run the complete length of the 48 in. rod. This allows for flexible positioning and connection at any point along the rod within a structural assembly.

Does this rod have any protective coating?

No. The ATRM9-4 is uncoated black steel with no protective finish applied. It is suited for interior structural installations where an exterior coating is not required by the design.