I cracked the wingknobs underneath my R&R cart. Got replacement knobs from the present manufacturer but they're too big. Called the company and they said there was a "re-design" of the R&R cart. One of the "casualties" was the "wingknobs."

So.....be aware that original parts for the older R&R carts might no longer be available.

i just threw my old R&R out and bought a newer model they are cheap enough and a must have necessity.