Kenko KSUR-6782 camera lens adapter

67-82mm Step Up Ring Stepping rings, also known as adaptor rings, allow the use of filters and accessories that are slightly larger or smaller in size than the front screw thread of the lens.

Step-Up rings in particular provide a way to fit a larger diameter filter or accessory onto a lens with a smaller thread diameter. The Step-Up ring screws onto the lens's front thread and provides a larger thread which can then be used for attaching other elements, including more Step-Up rings.