Every RVer has to deal with un-level campsites from time to time. Even if your RV is equipped with a leveling system, some sites are so sloped you just can't get your rig level. This is why RVers carry leveling blocks, also referred to as jack pads, stacker blocks or stabilizer pads. Whatever you call them, they all serve the same purpose: allowing you to level your RV on a sloped campsite. They also help keep jacks from sinking into soft surfaces. Here is a rundown from the RV Geeks about leveling blocks, including ones they consider the best.