I have the semi-automatic HWH Levelers on my 'C'. Because my RV is pretty close to the ground, I bought the kick down type. All four go from horizontal to vertical at once. Then a screen that I can see from the driver's seat lights up a button for either front, rear, left or right pair. I push the button that's lit until the light goes out. Then it usually lights up a different light and I repeat the process. When all the lights are out, I'm level. Expensive, but they sure are handy when its raining or cold outside.