The 55-72mm Magnetic Step-Up Ring from Freewell allows you to screw threaded filters onto compatible lenses or magnetically adapt Freewell magnetic filters.

Filters that have 72mm rear threads can be screwed onto lenses featuring 55mm front threads. Alternatively, for magnetic attachment, first screw this adapter onto a lens that has 55mm front threads, and then magnetically attach Freewell's 72mm magnetic filters onto the front of this adapter ring.