Class 5 stands for a product that has ¾” rock and minus/grit that packs around the ¾” rock to hold it in place. To be installed correctly so that it has longevity, it needs to have a permeable base fabric to keep it from sinking into the subsoil. It then needs to be compacted (driving over it does not compact it well enough) needs to be done with a vibratory drum compactor. The area also needs to have proper grade so that water drains away and does not sit.