I have good news! I was able to reach out to my contacts at SnapPad and they tell me that the SnapPads # SP84FR4 you were looking at will fit on the 10-1/4" round concave feet of your 2018 Winnebago motorhome. The springs won't come into play since these fit directly onto the outside and bottom of the feet and will help provide a larger footprint to keep your landing gear from sinking into the ground. view full answer...