I bought these to upgrade my Roomba E6 casters. The original casters that came with my Roomba were two different styles. I've attached a picture of the dark green roller I'm having an issue with. The ribs on them get torn by objects all the time, and for that reason I have a third set of spare wheels. However, the other reels show no signs of wear and are tangle resistant. When I found out that other Roomba models have two of these tangle-free casters, I began to wonder if they would be sizeβ¦