It is an adjustment for the "pitch" of the awning. And yes, you probably shouldn't change them if above a slide out. I think that not being able to slant it more kinda sux. But that's just the way it is.
You do not want rain water to pool in the middle of the shade. The weight of the water will eventually stretch where the water is and then make pooling worse. Mine pooled with the MH being level. I had to slightly adjust the pitch; which worked.
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Gale & Hank- 2012 Berkshire 390BH
We were going to take our TT back to the dealership this fall to adjust the awnings. Of course we were dreading that service visit... I will check to see if we have this adjustment available. Is this something easy to change? We are not mechanically inclined beyond the basic screwdriver.. Btw, we have a W and electric awnings that look like these. Not over a side out but they pitch up do not much shade from them. Manual adjustments by tightening the knobs don't hold.