Camco FasTen RV Leveling Blocks - 8.5” x 8.5” x 1”- 10-Pk - Made in the USA

Why it's worth it

These interlocking blocks stack to whatever height your low tire needs, then lock together so they can't skate apart under load. They're made in the USA, they carry with a twist-in T-handle, and they work under stabilizer jacks and tongue jacks as well as tires.

The interlock is the whole point. Loose blocks squirt out sideways when a tire climbs them, which is how people end up chasing a yellow square across a gravel pad. These grip each other, so a three-high stack stays a stack. Camco says not to build higher than about four and a half inches, and that's a limit worth respecting on a windy night.

Ten blocks is enough for a typical campground pad. Guides for new owners generally suggest two blocks per side for a normal site, and double that if you camp off-grid on dirt. With ten, you can put a two-high stack under both tires on one side and still keep a couple in reserve for the tongue jack. Two sets is the answer for a long fifth wheel.

From our review of 6 rv leveling blocks

What we like

• +The interlock is the whole point
• +Ten blocks is enough for a typical campground pad
• +The T-handle sounds like a gimmick until you've carried blocks in the rain
• +They're not just tire blocks

What to know

• –Stacking takes a few minutes, and you'll do it twice — once to guess the height, once to fix your guess
• –Each block is only about an inch and a half thick, and the stack limit is about four and a half inches