This lens is fully manually controlled - both aperture and focus are controlled on the lens and there are no electronics. The aperture ring is not de-clicked, so there are hard stops when changing the aperture. I'm happy to include any focus rings or belts that may be of any help. The lens is suitable for full-frame sensors and has a filter thread of 77mm. Official Description: The Samyang 35 mm f1.4 AS UMC lens was designed to suit most popular SLR and DSLR cameras. On a full frame camera the 35mm focal length has universal applications, the lens is bright / fast wide-angle lens perfect for landscape, journalism and general shooting applications, including low light photography. When mounted on a camera with APS-C sensor, will become a popular, multitasking 50mm prime lens, perfect for general photography including low light photography. When mounted to cameras with the 4/3rd system, the Samyang 35 mm F1.4 AS UMC will turn into a short, bright portrait lens with 70mm focal length equivalent. The wide apertures of the 35mm provide beautiful bokeh, (the character of out-of-focus areas) which is perfect for portrait type applications, or photography where ultra smooth out of focus backgrounds or foregrounds is preferred. This technique helps to separate the subject from the background giving very pleasing and professional results.... Specifications: Focal Length: 35mm Max Aperture: f/1.4 Lens Format: APS-C, Full Frame Lens Type: Wide Lens Mount: Sony E Type: Photo, Video Weight: ~2kg