The Simpson 1/4 in. x 4 in. Mechanically Galvanized Split-Drive Anchor is a one-piece mechanical expansion anchor from Simpson, engineered for fast, reliable fastening into concrete, grout-filled block, and stone. As the anchor is driven into a pre-drilled hole, the split-type expansion mechanism on the working end compresses and exerts outward force against the walls of the hole, creating a secure mechanical hold without adhesives or additional hardware. The countersunk head sits flush with the surface for a clean, low-profile finish, making this anchor a trusted choice for contractors and specifiers tackling demanding structural applications in dry, interior, and non-corrosive environments.

Key Features

• One-piece split-drive expansion design - the self-contained anchor installs with a single driving step, eliminating extra components and speeding up installation on the job site
• Countersunk head profile - sits flush with the work surface once driven, providing a clean finish when attaching wood or light gauge steel to concrete or masonry
• Compatible with concrete, grout-filled block, and stone - broad base-material compatibility gives contractors flexibility across a wide range of masonry fastening tasks
• Mechanically galvanized carbon steel construction meeting ASTM B695, Class 55, Type 1 - the zinc coating applied through a mechanical process meets a recognized industry standard, offering a consistent level of corrosion resistance appropriate for interior, non-corrosive conditions
• Matched 1/4 in. drill bit diameter - anchor diameter and required drill bit diameter are identical, simplifying tool selection and reducing the chance of mis-drilling on site
• Dry and interior environment rating - clearly defined environmental limits help specifiers select the right anchor for code-compliant installations without guesswork

Why This Product

• Engineered for demanding structural applications - Simpson designs these mechanical anchors for optimum performance under rigorous conditions, making them a dependable choice when a secure, lasting hold in concrete or masonry is critical
• No-fuss, one-piece installation - the split-drive mechanism compresses and locks automatically as the anchor is driven, so there are no separate expansion sleeves or setting tools required, keeping workflows efficient
• Flush countersunk finish expands application options - the low-profile head allows the anchor to be used wherever a protruding fastener head would be impractical, including wood-to-concrete and light gauge steel-to-concrete connections
• Standardized galvanizing provides confidence in coating quality - mechanically galvanized to ASTM B695, Class 55, Type 1, the finish offers a verifiable, specification-grade level of protection suited to dry interior masonry environments

Specifications

• Manufacturer: Simpson Strong-Tie
• MPN: CSD25400MG
• Diameter: 1/4 in.
• Length: 4 in.
• Head Type: Countersunk Head
• Head Diameter: 1/2 in.
• Drill Bit Diameter: 1/4 in.
• Material: Carbon Steel
• Coating: Mechanically Galvanized
• Finish: Mechanically Galvanized
• Galvanizing Standard: ASTM B695, Class 55, Type 1
• Packaging: Packs of 100 and Cartons of 400

Approved Applications

• Fastening into concrete substrates
• Fastening into grout-filled concrete masonry units (CMU)
• Fastening into stone
• Attaching wood to concrete or grout-filled block surfaces
• Attaching light gauge steel to concrete or grout-filled block surfaces
• Dry, interior, and non-corrosive environments only

Frequently Asked Questions

What base materials can the Simpson CSD25400MG Split-Drive Anchor be installed in?

This anchor is designed for installation in concrete, grout-filled block, and stone. It is not intended for use in hollow CMU or brick without grout fill, and should only be used in dry, interior, and non-corrosive environments.

What drill bit size is required to install the CSD25400MG anchor?

A 1/4 in. diameter drill bit is required to pre-drill the hole for this anchor. The anchor itself has a 1/4 in. diameter and 4 in. length.

What does the mechanically galvanized finish mean, and what standard does it meet?

Mechanically galvanized means the carbon steel anchor has been coated through a mechanical process that applies a zinc layer for corrosion resistance. This coating meets ASTM B695, Class 55, Type 1 specifications. The anchor is suitable for dry, interior, and non-corrosive environments only.

How does the split-drive expansion mechanism work?

The CSD25400MG is a one-piece anchor with a split-type expansion mechanism located on its working end. As the anchor is driven into the pre-drilled hole, the split expansion section compresses inward and simultaneously exerts outward force against the walls of the hole, creating a secure mechanical grip without the need for nuts, bolts, or adhesives.

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