ZHONG YI OPTICS Lens Turbo II M42-FX M42 Mount Lens - Fujifilm X Mount Focal Reducer Adapter This is a focal reducer lens-equipped mount adapter for attaching M42 mount lenses to Fujifilm X mount camera bodies. Purchased new and stored in a dehumidified storage box. I'm selling it because I've only used it a few times. There are minor scratches from attaching and detaching the lens, but the lens is in good condition because it was stored in a dehumidified storage box. This is a private sale, so please understand. If you have any questions, please feel free to contact me. Accessories: Front and rear caps, outer box, instruction manual [Excerpt from the official website] The following is an explanation from Focus Camera. The Lens Turbo II M42-FX is a mount adapter equipped with a focal reducer lens for attaching M42 mount lenses to Fujifilm X mount camera bodies. With a high-quality 3-group, 4-element reducer (reducing optical system) lens, the focal length is reduced to 0.726x (※). This allows shooting with the original angle of view of the lens (almost full-frame) even with an APS-C camera. In addition, the light-gathering effect of the focal reducer lens makes the F-value one stop brighter, which is also a feature that allows you to gain shutter speed. When used with a 50mm lens: 50mm x 1.5 (APS-C focal length magnification) x 0.726 (Lens Turbo focal length magnification) = 55mm equivalent angle of view When used with a 35mm lens: 35mm x 1.5 (APS-C focal length magnification) x 0.726 (Lens Turbo focal length magnification) = 38mm equivalent angle of view Compatible lenses: M42 mount lenses Compatible models: Fujifilm X mount cameras Compatible image sensor size: APS-C Total length: 30mm Diameter: Φ64mm Weight: Approximately 160g