• 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)
• 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
Best Jack Block: Why It's Different
The jack block that sticks on, stays centered, and makes your parked trailer 90% more stable.
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.
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.
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.
Works on everything. Stores in seconds
Compatible with most standard tongue jacks and post jacks. Stackable, compact, and light enough to toss in a bag.
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.
Two heights. One simple decision.
4" BLOCK · 4" Magnetic Jack Block
Best For
5th wheels, large travel trailers, and any rig where you want maximum stability with minimal lift.
8" BLOCK · 8" Magnetic Jack Block
Best For
Travel trailers, campers, and any setup where your jacks need extra height to reach uneven or sloped ground.
Most owners need 4 blocks total — one per stabilizer jack.
Feature 01 of 4
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.
Payoff Hands-free setup in under 30 seconds — even on a slope.
Feature 02 of 4
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.
Payoff Up to 90% less trailer movement once you're parked.
Feature 03 of 4
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.
Payoff Fits virtually every RV, 5th wheel, and travel trailer jack on the market.
Feature 04 of 4
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.
Payoff Made in Idaho Falls. Backed by a lifetime warranty.
Compared to Camco, Lynx Levelers, OX BLOX, and other trailer jack blocks, the Andersen Trailer Jack Block is the only option with patented magnetic alignment that snaps to your jack hands-free. It offers the highest single-block weight rating at 30,000 lbs (4" version), a 12-inch flared base for maximum ground contact, and a lifetime warranty — all made in Idaho Falls, USA with over 100,000 units sold.
| Feature | Ultimate 5th Wheel Connection | Other Trailer Jack Brands |
|---|---|---|
| Stays in Place | ✓ Patented magnets snap to the jack — hands-free alignment | ✗ Camco, Lynx, and most jack pads have no magnetic alignment |
| Setup Time | ✓ Under 30 seconds — magnets self-center the block | ✗ Lego-style blocks (Lynx) and interlocking pads (Camco) require manual placement |
| Weight Capacity (Single) | ✓ 30,000 lbs (4") — highest single-block rating in the category | ✗ Camco rated to 6,000 lbs; OX BLOX rated to 10,000 lbs; VEVOR rated to 6,000 lbs |
| Base Diameter | ✓ 12" flared base — 4× more surface area than a standard 6" jack foot | ✗ Camco pads are 8.5" × 8.5"; most competitors smaller than 10" |
| Trailer Stability | ✓ Up to 90% less rocking — solid one-piece molded base | ✗ Multi-piece interlocking systems can shift under load |
| vs. 2x6 Lumber | ✓ Won't rot, splinter, warp, or absorb grease | ✗ Wood blocks absorb water, grease, and mold over time |
| Storage Footprint | ✓ Stackable, nestable, doubles as a step-stool | ✗ Most jack pads require separate storage straps or bags |
| Warranty | ✓ Lifetime warranty — we replace it, you pay shipping | ✗ Most competitors offer 1-year or limited warranties |
Still not sure which fits? Let's match you.
We've spent 30+ years building products our family is proud to send out the door.
What if it breaks?
Cracks, splits, magnet fails — we replace it. Just pay shipping. Camco gives you 1 year. We give you forever.
Cheap import?
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?
Order today, it leaves the warehouse tomorrow. No 2-week third-party fulfillment delays. Ready for your next trip.
Will it fit my 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.
Free shipping over $50 · Lifetime warranty · Ships from Idaho Falls
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.
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