Question about Klotzli folders, pivot area screw?

[Applejacks]

I am in love with the Klotzli ACC folder. But I am a bit thrown off by the silver round item on the handle right at the pivot point. It seems all the Klotzli folders have them. What is it? And to owners of Klotzli's does it take away from the visual aesthetics of it in person? Thanks.