This would be referring to the ball end. The end with the pin should feel tight due to tolerances and will loosen themselves up with normal use. I found that I did not have to size those particular ball links. Be sure that you're putting them onto the balls the right way. If you look closely there is a larger diameter hole side which is what should be pressed onto the ball. The other side is the smaller side like a normal link and should be facing out.
Regards,
Brandon Bartolomucci
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