4x4 Screw Jacks 2 Pack Adjustable Jack Posts - Heavy Duty Support

In this review the reviewer looks at the 4x4 Screw Jacks 2 Pack and finds them best suited for DIYers and professionals who need robust, adjustable temporary or permanent support for lumber and structures. The single biggest reason to buy is the combination of a wide adjustable range and a very high load capacity, which makes these shore jacks reliable for basement, crawlspace, stairwell, shed, and construction uses where controlled lifting and leveling of 4x4 posts is needed.

Key Features

• Fit for 4x4 lumber: Designed to accept standard nominal 4x4 square lumber (3.5in sq) so you can use readily available posts for support.
• Wide adjustable height: Adjustable height range lets users set support between about 13.2in and 18.7in, offering flexibility for different leveling and shoring tasks.
• High load capacity: Rated up to 24,000 lbs maximum load capacity, providing heavy duty support for demanding residential and commercial jobs.
• Secure base plate: The 3.5 x 6in base plate includes multiple mounting holes for fixing the jack to a floor or beam for stable, long-term installations.
• Swivel top for alignment: The M22 swivel bar lets you rotate and fine tune the top plate during installation to get the post aligned quickly.

Who It's For

The 4x4 Screw Jacks are aimed at homeowners tackling basement or crawlspace leveling, contractors doing temporary shore supports during repair work, and farmers or builders who need a portable heavy duty post support. They are especially useful when standard 4x4 lumber is part of the support system and a high load rating is required.

Those who want a tool-free micro adjustment system and fast setup will appreciate these jacks, but if you need support for nonstandard beam sizes or require adjustable heights outside the 13.2in to 18.7in range you should look at alternative jacking systems designed for different lumber dimensions or greater extension.

Pros & Cons

Pros

• Solid compatibility with standard 4x4 posts makes sourcing replacement lumber easy.
• Generous load rating up to 24,000 lbs gives confidence for heavy structural support tasks.
• Multiple mounting holes on the base plate allow secure installation for semi-permanent use.
• Simple height adjustment and a swivel top speed installation and alignment.

Cons

• Height adjustment limits mean it is not suitable when you need support shorter than about 13.2in or taller than about 18.7in.

Specifications

Fit	Standard / nominal 4x4 lumber (3.5in sq)
Adjustable height range	13.2in - 18.7in
Base plate size	4in x 4in x 0.28in
Base plate mounting holes	Four 0.6in and two 0.3in holes
Swivel bar (top)	M22, 12in height swivel
Maximum load capacity	Up to 24,000 lbs

Our Verdict

The 4x4 Screw Jacks 2 Pack is a practical, heavy duty option for anyone who routinely works with 4x4 posts and needs dependable adjustable support. With a strong 24,000 lb capacity, secure base plate options, and a convenient swivel top, these jacks are good value for foundation, crawlspace, and temporary shoring tasks where the specified height range matches the job.

Frequently Asked Questions

Will these fit standard 4x4 lumber?
Yes. They are designed for nominal 4x4 square lumber measuring about 3.5in square.

Can the base plate be mounted permanently?
Yes. The base plate includes multiple mounting holes to secure the jack to a floor or beam, though mounting hardware is not included.

How much weight can each jack hold?
Each jack is rated with a maximum capacity up to 24,000 lbs for heavy duty support applications.