I got my caps from Year One back in 2011. Out of the 4 caps in the set I got one of these oddball ones. It was really thin metal and didnt fit the rim correctly...too loose & would pop off.
I called Year One about it and they sent me another set....guess what? It had one of those oddball caps in it as well!
made a good set of 4 and returned the rest.

Looking at the pictures I believe the bad cap was the dull on the inside one...the cap on the right in both the pics....


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