What is the name of the kind of stationery fasteners used to let papers move?

I am not sure I am explaining it right but I am thinking of a fastener used between two pieces of hard board (cardboard) that lets them move or spin. It is similar to a brass fastener but not with one end being pointy. Imaging a fastener with the head of a brass fastener on both sides. I don't know if that makes sense.

It is a stationery fastener that lets the things it holds together spin freely. It functions similarly to a Lazy Susan in woodworking but on a much smaller scale for papers or cardboard.

Pictures of it would be appreciated. Thanks.