The Camco FasTen XL Leveling Blocks allow you to stack the interlocking blocks to the desired height for safe and easy leveling. The new, larger size has an increased weight capacity of blocks individually and in a stack, and also provides more surface area for leveling.
I really like the larger size of these, they seem very sturdy. I even like the darker color, my motorhome is black, tire covers are black, so now I don't have this stack of neon-yellow levelers showing under the tire. All in all, a good purchase, just what I needed.