To make the most durable step-up ring Breakthrough Photography simply took the craftsmanship, build quality and durability of their professional filters and adapted it to the step-up ring. Breakthrough Photography manufacture this step-up ring with brass and then apply a matte black electroplated finish, which withstands corrosion and other abrasive elements often encountered in outdoor photography. The result of better construction and materials, combined with a proven design makes this step-up ring the most durable and functional step-up ring available to professional outdoor photographers. | Breakthrough Photography | | 46mm to 60mm CNC Brass Step-Up Ring | Best Buy