The Simpson 1/2 in. x 7 in. Hot-Dip Galvanized Retrofit Bolt from Simpson is a precut threaded rod supplied with a nut and washer, engineered for use with anchoring adhesives to anchor into existing concrete and masonry. When paired with a Simpson Strong-Tie adhesive, this retrofit bolt delivers a complete engineered anchoring system built to handle the demands of structural retrofit and repair applications. Each end of the threaded rod is stamped with the rod length in inches and color-coded to indicate the grade or type of steel, and for 1/2 in. diameters and larger, the distinctive No-Equal symbol is also stamped, making post-installation identification quick and easy.

Key Features

• Handles both tension and shear loads - provides reliable structural performance across multiple load types, making it well suited for demanding retrofit anchoring connections in concrete and masonry.
• Coarse thread type - promotes strong mechanical interlock with anchoring adhesive, supporting a secure and consistent bond within the base material.
• End-stamped rod length with color-coded steel grade identification - lets installers confirm bolt specifications and steel type at a glance after installation, reducing the risk of field errors.
• No-Equal symbol stamped on 1/2 in. diameter and larger rods - provides an additional layer of post-installation verification, giving inspectors and contractors confidence in the installed product.
• Hot-dip galvanized coating and finish - delivers enhanced corrosion resistance compared to standard zinc plating, helping extend service life in exposed or moisture-prone environments.
• Nut and washer included - supplies all the hardware needed to complete the connection, simplifying procurement and jobsite preparation.
• Designed as part of a complete engineered anchoring system - when used with a compatible Simpson Strong-Tie adhesive, the bolt functions within a coordinated, tested assembly rather than as a standalone component.

Why This Product

• Engineered specifically for retrofit anchoring - unlike standard threaded rod sold in bulk, this precut bolt is purpose-built for anchoring into existing concrete and masonry, arriving ready to use with the appropriate hardware already included.
• Built-in post-installation identification - the stamped rod length, color-coded steel grade marking, and No-Equal symbol give contractors and inspectors a straightforward way to verify the correct bolt is in place, adding accountability to the finished installation.
• Hot-dip galvanized protection for long-term durability - the hot-dip galvanized finish provides a thick, durable corrosion-resistant barrier suited for retrofit projects where the anchor will be exposed to environmental conditions over its service life.
• Part of a complete Simpson Strong-Tie anchoring system - pairing this bolt with a Simpson Strong-Tie adhesive creates a fully engineered anchoring assembly, giving engineers and inspectors a consistent, documented system rather than a mix of unrelated components.

Specifications

• MPN: RFB#4X7HDG
• Brand: Simpson Strong-Tie
• Diameter: 1/2 in.
• Bolt Length: 7 in.
• Thread Type: Coarse
• Coating: Hot-Dip Galvanized
• Finish: Hot-Dip Galvanized
• Country of Origin: United States

Approved Applications

• Anchoring into existing concrete and masonry when used with Simpson Strong-Tie adhesives
• Structural connections requiring both tension and shear load resistance
• Retrofit anchoring projects where a complete engineered anchoring system is required

What's Included

Each pack contains (1) RFB#4X7HDG Hot-Dip Galvanized Retrofit Bolt, Precut threaded rod (1/2 in. x 7 in.), Nut, Washer.

Frequently Asked Questions

What is the Simpson Strong-Tie RFB retrofit bolt used for?

The RFB retrofit bolt is a precut threaded rod designed for use with anchoring adhesives to anchor into existing concrete and masonry. When used with a Simpson Strong-Tie adhesive, it provides a complete engineered anchoring system.

What size is the RFB#4X7HDG?

This retrofit bolt has a diameter of 1/2 in. and a bolt length of 7 in., with a coarse thread type.

How do you identify the RFB#4X7HDG after installation?

Each end of the threaded rod is stamped with the rod length in inches and is color-coded to indicate the grade or type of steel. For 1/2 in. diameters and larger, the distinctive No-Equal symbol is also stamped, making post-installation identification quick and easy.

What type of corrosion protection does the RFB#4X7HDG have?

The RFB#4X7HDG features a hot-dip galvanized coating and finish, providing a high level of corrosion resistance suitable for demanding installation environments.

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