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I used a vise grip and long nose pliers to pull it straight out (without turning), clamping on the middle ring portion at different points. Perhaps mine wasn't very difficult to pullout because there was already a break in the seal since water started to flow out when I unscrewed the cover. Normally the white plastic thing is attached to the cover but is allowed not to turn while the cover is unscrewed. The connection between the two is weak in my opinion.