Shoot 600 film in an original SX-70. A stock SX-70 is set up for slower SX-70 film, so 600 film comes out about two stops too bright. Our 37mm neutral density filter cuts those two stops so 600 film exposes correctly. Mount it to the SX-37 Adapter and shoot. Bought your SX-70 from us? You don't need this. Every SX-70 we sell has an OpenSX70 board and already shoots both SX-70 and 600 film. This filter is for SX-70s from anywhere else that still have their original electronics. Two reasons to bother: Polaroid releases most of its special edition films in 600 only, while the SX-70 gets core color and B&W. And 600 film is stocked nearly everywhere, so you're not hunting for SX-70 stock. Includes a protective filter case. Filter size: 37mmOptical density: 0.6 (2 stops)Materials: Gel, metalWeight: 2.2 oz Designed in collaboration with Retrograde Engineer. Part of our Instant Optics line.