43mm 52mm Step Up Ring

General Brand 43mm-52mm Step-Up Adapter Ring (Lens to Filter)

B&W 65069483 B&W B & W Step-Down Adapter Ring From Filter 52MM To Lens 43 X 0.75.

Allows you to use larger size filters on lenses with a smaller diameter thread. The first number is the size that screws into the lense, the second number is the filter size.