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Trailer Jack Block
• Built-in magnets instantly attach to the jack, so there is no need to double-check and adjust each jack block.
• A 2-1/2” recessed post hole works great with post jacks
• Stackable for extra height (no more than 2)
Weight Rating & Specs
• Each 8" Trailer Jack Block is rated to up to 8,000 lbs or 1,500 lbs when double stacked
• Each 4" Trailer Jack Block is rated to up to 30,000 lbs or 20,000 lbs when double-stacked
• 12” diameter base, 10“ diameter top
• Top of the jack block includes a 9-1/8” diameter recessed pad and a 2-1/2” recessed post hole for post jacks
• Weighs 5.3 lbs
• Made in the USA
• Covered under lifetime warranty
Click the link to find out our product warranty information
VISIT WARRANTY PAGE
USA Built: Why It's Different
No More Wobbly Trailer. Set It and Forget It.
The jack block that sticks on, stays centered, and makes your parked trailer 90% more stable.
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Magnets do the work — no guessing, no adjusting.Snap it to your jack foot before you lower. It stays centered automatically. No more kicking a wood block into position, watching it shift, and starting over.
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Your trailer stops moving. Your jack stops wearing out.Less jack extension means less stress on the mechanism over time. The wide base also prevents sinking into soft ground — your campsite stays clean.
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Up to 30,000 lbs. rated. Strongest Jack blocks available.The 4" block holds up to 30,000 lbs single — more than most trailers will ever need. Stack two for extra height up to 20,000 lbs. Made in Idaho Falls, Idaho.
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Works on everything. Stores in secondsCompatible with most standard tongue jacks and post jacks. Stackable, compact, and light enough to toss in a bag.
Stop Stacking Wood. Start Sleeping Still.
Every RVer's seen it: someone walks across the trailer and the whole rig sways. The fix isn't bigger jacks — it's a wider, magnetic base that won't shift, sink, or slide off the moment your jack hits dirt.
- 2x6s slide off the jack pad on uneven ground
- Stacked blocks shift when someone walks inside
- Jacks extend too far — gears wear out faster
- Wet, greasy lumber rolling around your basement
Two heights. One simple decision.
- Highest weight rating in the lineup
- Compact 4" lift — less jack travel
- Stack two for 8" total height
- Built-in magnets snap to your jack pad
- Recessed post hole for post jacks
- Bigger lift for shorter jack travel on uneven sites
- 12" diameter base for maximum ground contact
- Stackable up to 14" total height
- Doubles as a step-stool when not towing
- Resists dirt, grime, and oil
Most owners need 4 blocks total — one per stabilizer jack.
Four parts. One rock-solid base.
Built-In Magnet Lock
Patented magnets embedded in the recessed pad snap to your jack foot the second they touch — holding the block dead-center as the jack lowers. No bending. No kicking it back into place. No wood that slides off the moment weight hits it.
12" Footprint Base
A flared 12-inch base spreads the load across roughly 4× more surface area than a 6" jack foot alone. On gravel, dirt, or soft pavement, that's the difference between a stable rig and one that sinks an inch overnight.
9-1/8" Recessed Pad
The recessed top cradles up to a 9-1/8" round jack foot and includes a 2-1/2" post hole — so it works with both stabilizer jacks and post-style jacks without adapters or guesswork.
30,000 lb Shell
Heavy-duty molded plastic engineered for up to 30,000 lbs (4" version, single block). Resists dirt, grime, oil, and UV — and won't rot, splinter, or warp like the 2x6 currently rolling around your basement.
Why owners ditch Other Products for Andersen.
We've shipped over 100,000 of these. Here's exactly why owners switch from Camco Stabilizers, Lynx Levelers, Beech Lane blocks, SnapPad, and the classic stack of 2x6s.
Stop stacking. Start stabilizing.
We set out to build the best Trailer Jack block.
We've spent 30+ years building products our family is proud to send out the door.
What if it breaks?
Lifetime Warranty
Cracks, splits, magnet fails — we replace it. Just pay shipping. Camco gives you 1 year. We give you forever.
Cheap import?
Made in Idaho Falls
Family-owned and 100% American-made — molded, packed, and shipped from our Idaho Falls facility. Not a single part sourced overseas.
Will it arrive in time?
Ships in 24 Hours
Order today, it leaves the warehouse tomorrow. No 2-week third-party fulfillment delays. Ready for your next trip.
Will it fit my jack?
Fits Virtually Every Jack
9-1/8" recessed pad + 2-1/2" post hole = compatible with stabilizer jacks, post jacks, electric, and hydraulic. If yours doesn't fit, we'll refund you.
Ready for a steadier rig?
Free shipping over $50 · Lifetime warranty · Ships from Idaho Falls
Other Recommended Products
No questions match your search.
A trailer jack block provides a stable base under your trailer jack to improve leveling, reduce jack travel, and prevent sinking on soft ground.
The best trailer jack block is one that provides stability, ease of use, and consistent alignment. The Andersen Trailer Jack Block stands out because its built-in magnetic design keeps it perfectly positioned while reducing setup time and improving overall trailer stability.
Yes, the magnets attach directly to the jack foot and hold the block centered during setup.
Yes, the Andersen Trailer Jack Block is considered one of the best trailer jack block options because it stays aligned with built-in magnets, provides more consistent stability, and eliminates shifting or stacking issues common with wood blocks.
Yes, it works great as an RV jack block for travel trailers, campers, and utility trailers.
It is compatible with most standard trailer tongue jacks and post jacks.
Yes, it can be stacked up to two blocks for additional height when needed.
The Andersen Trailer Jack Block is rated up to 30,000 lbs for the 4" version and 8,000 lbs for the 8" version, giving it one of the highest weight capacities among RV and trailer jack blocks.
Yes, it creates a wider, more stable base that improves support on dirt, gravel, grass, and other uneven surfaces.
Yes, reducing jack extension helps limit strain and wear over time.
Yes, it weighs just over 5 lbs and is compact enough to store easily in your vehicle or trailer.
Yes, it helps you set up faster by reducing jack travel and eliminating repositioning, which is why many trailer owners consider it one of the best jack blocks for quick setup.
The Andersen 4" Trailer Jack Block is rated up to 30,000 lbs, making it one of the strongest trailer jack blocks available while still offering easy setup and magnetic alignment.
