Fence Post Holder Ground Spike for Concrete Deck 4x4 Post Anchor - 8

In this review the Fence Post Holder Ground Spike is evaluated for homeowners and contractors who need a robust method to set 4x4 posts into new concrete. The main reason to consider this product is its construction for embedding into wet concrete so the base becomes an integrated, heavy-duty anchor; that single approach simplifies deck and fence post installation and eliminates complicated on-site plate setting. The reviewer tested the concept against typical usage needs and focused on build quality, fit for 3.5in x 3.5in posts, and whether the anchor stays firmly fixed once concrete cures.

Key Features

• Fit: Precisely sized to accept a 3.5in x 3.5in wood post so standard 4x4 posts slide in with minimal trimming.
• Durable material: Made from high-strength steel with a black powder coat to resist outdoor exposure and reduce visible corrosion.
• Firm anchoring: Built with four 1/2in diameter anchor rods at 7in length that lock the base into concrete for a secure hold.
• Wet concrete installation: Designed to be set into wet concrete so the anchor becomes part of the foundation as it cures, simplifying alignment and strength.
• Practical pack size: Sold as an 8 pack, suitable for multi-post projects like short fences, railing runs, or small deck supports.

Who It's For

This product is best for DIY homeowners, deck builders, and fencing contractors who pour new concrete footings and want a straightforward way to anchor 4x4 posts. It works well on projects where posts must be fixed solidly into a slab or footing and where embedding the anchor during the pour is acceptable.

It is less suitable for retrofit jobs where posts must be anchored to existing concrete without breaking up the slab, or for applications that require adjustable post height after concrete cures. For those scenarios, a surface-mounted base would be a better choice.

Pros & Cons

Pros

• Heavy gauge steel and powder coating provide good long-term durability in outdoor conditions.
• Four substantial 1/2in anchor rods and 7in length give a reliable mechanical connection into concrete.
• Precise sizing for 3.5in x 3.5in posts means less on-site trimming and a snug fit.
• Sold as an 8 pack, providing value for small runs of posts or multi-post projects.

Cons

• Requires pouring or disturbing concrete since it must be set in wet concrete, so not ideal for retrofit without new footings.
• Fixed height and no post-adjustment feature once concrete cures, limiting post leveling options later.

Specifications

Compatible post inner size	3.5in x 3.5in
Base size	4in x 4in
Material	High-strength steel
Finish	Black powder coated
Anchor rods	4 rods, 1/2in diameter x 7in length
Pack quantity	8 per pack

Our Verdict

The Fence Post Holder Ground Spike is a practical, value-oriented anchor for anyone pouring new concrete footings who needs a sturdy, permanent mount for 4x4 posts. Its heavy-duty steel construction and dedicated anchor rods deliver reliable performance, and the 8 pack makes it cost-effective for small projects. Choose this if you plan new concrete pours and want a simple, durable post anchoring method.

Frequently Asked Questions

Can these be installed after the concrete has cured?
They are designed to be set in wet concrete; installing them after concrete cures would require drilling or creating a new footing and is not the intended use.

What post size fits this anchor?
The holder accepts a 3.5in x 3.5in wood post, which corresponds to standard 4x4 lumber nominal sizing.

Is the coating weather resistant?
The product uses a black powder coat over high-strength steel to improve resistance to outdoor weather and slow surface corrosion.