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1/4" x 3-1/2" Split Drive Flat Zinc Plated, 100/Box

$30.00 per Box of 100
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   Availability: In Stock
  Questions? Email Mike

SKU: SDF14312

CONFAST® - 1/4" x 3-1/2" Split Drive Flat Zinc Plated

1/4" x 3-1/2" Split Drive Flat Zinc Plated (100 pcs per box) are used for fastening wood to solid concrete. In stock and all orders will be received in 1 to 3 business days when shipped in the continental United States.

  • Bit size 1/4"
  • Minimum embedment 1-1/8"
  • Tamper resistant head
  • Indoor use only - zinc plated
  • Pre-expanded friction type anchor
  • Not for use in vibratory loads
  • 1/4" in. is the diameter x 3-1/2" in. is the length
  • Spacing - a minimum 2-1/2"
  • All order shipped in continental U.S. over $25.00 ship freight free
Products specifications
Bit Size 1/4"
Minimum Embedment 1-1/8"
2000 PSI Concrete - Pull-Out (lbs.) * 990
2000 PSI Concrete - Shear (lbs.) * 1248
Type Male
Primary Concrete only
Diameter 1/4"
Length 3-1/2"
Material Carbon Steel Zinc Plated
Environment Dry
Box Qty 100
Minimum Spacing 2-1/2"
Minimum Edge Distance 1-1/4"
Maximum Fixture Thickness 2-3/8"
Minimum Fixture Hole Diameter (In Place) 3/8"
Head Type Flat Countersunk
Brand Name CONFAST

The anchor is made from Carbon Steel, and is Zinc Plated. This anchor is designed for use in Concrete only, and should never be used in block or brick base material.

The anchor is designed for use in a Dry environment.

Head Style
The anchor is a Flat Countersunk head and is designed to prevent the head from protruding above the surface of the item being attached.

Hole Diameter/Bit Diameter
The anchor requires a 1/4" hole to be drilled in the base material (Concrete only). The hole should be drilled with carbide tipped bit that meets ANSI standards and used in a hammer drill.

Diameter of Anchor
The diameter of the anchor is 1/4".

Length Anchor
The length of the anchor is 3-1/2"

The anchor is packaged with 100 pieces per box .

Minimum Embedment
The minimum anchor embedment into the concrete is 1-1/8". Therefore, the anchor must be installed so that a minimum of 1-1/8" of the anchor is embedded into the concrete.

Depth of Hole
The depth of the hole that is required for the anchor should be a minimum of 1/2" deeper than the anchor will penetrate the concrete. This will allow space for dust created during the installation process to fall, which will prevent the anchor from bottoming out in the hole before full penetration into the concrete.

Maximum Fixture Thickness
The maximum fixture thickness or the maximum thickness of the material being fastened for a anchor is 2-3/8". This will ensure that the minimum embedment of 1-1/8" will be met.

Fixture Hole Diameter
The hole in the fixture or material being fastened must be larger than the designated diameter of the anchor. The 1/4" diameter anchor requires the hole in the fixture to be 3/8".

Spacing between Anchors
Each anchor must be spaced a minimum distance of 2-1/2" from each other when measured center to center.

Edge Distance
It is very important not to install the anchor any closer than 1-1/4" from an unsupported edge of the concrete.

Holding Values - Ultimate Load Values in 2000 PSI Concrete

Anchor Size

Minimum Embedment

Pull-Out (lbs.)

Shear (lbs.)

1/4" x 3-1/2"




Installing a 1/4" x 3-1/2" Split Drive Flat Zinc Plated
  1. Drill a 1/4" hole into the concrete using a carbide-tipped bit that meets ANSI Standards B212.15.
  2. Drill the hole a 1/2" deeper than the anchor will penetrate the concrete, making sure the minimum embedment requirements of 1-1/8" is met.
  3. The hole can be drilled while the fixture is in place. The minimum hole in the fixture for the 1/4" x 3-1/2" Split Drive Flat Zinc Plated is 3/8".
  4. Clean the hole with a wire brush, vacuum, compressed air, or a blow-out bulb.
  5. Insert the 1/4" x 3-1/2" Split Drive Flat Zinc Plated through the material to be fastened and into the hole, ensuring that the bottom of the head is sitting flush with the fixture plate.
  6. Hammer the anchor until the head of the anchor is tight against the item being fastened.
  7. Always use proper personal protective equipment per manufacturer's and OSHA instructions.


Product/Company Reviews

* The figures above indicate average ultimate tension and shear failure values. A safety factor of 4:1 or 25% of ultimate value is generally accepted as a safe working load. Reference should always be made to applicable codes.

* The bits are recommended by diameter and may not necessarily be the length needed for your application. Please make sure the usable length will work for your application. *

These bits work with the selected anchor
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