I looked at my limb pockets when it was tore down last week and couldn't grasp what was folded over on yours, could you specify what the issue was?

Inside my limb pocket I saw a white plastic shim with a slot in the middle for the limb bolt to slide through, kinda looked like teflon. But it looked way too thick to fold over and if it was I can only assume the limb would sit crooked. When I look at the assembled bow I can see a piece of black plastic sitting towards the rear, some sort of spacer.

p.s. mines still slow, but as I've said in the past- oh well. Live and learn.
65#, 29" draw, peep sight(no tube), ONE cat whisker on top, string loop w/ tied in nock, 418 grain arrow= 263-265 fps (both my chrony and the shops). Sound slow to any of you?
Maybe the new extra lubed limb pockets will fetch me another fps[:-]!