Here is what I came up with after trying to find information on HWH or HIGHLY WITHHELD & HIDDEN leveling systems. Searching on several search engines, even a browser I pay to search with, results are still vague. The hydraulic repair shop in a neighboring town has been trusted for years. I had one jack repaired for fewer than four hundred dollars. This is about the same as HWH but without the shipping charges. During the repair I was able to get the repair list of components needed. If anyone wants to remove their 62-pound jack and repairing it in there own shop, here is the parts list. The hardest part is the removal of the springs.