The Lensbaby Step-Up/Shade is a combination 37mm to 52mm step-up ring/lens shade that provides good light and flare blockage as well as a convenient way to use 52mm filters on Lensbaby lenses. Standard step-up rings do not provide the added benefit of the lens shade functionality, nor will they work on a Composer as they are too wide to fit into the Composer, preventing the focus ring from rotating fully.