This is a universal adapter for various systems. It works with all types of sensors. Made in a metal case, optic is glass. The lenses have neutral coating. The threaded mounting is 72/77/82 mm in diameter (on request). The adapter also has a 95 mm thread for a filter (macro filters can be used for shooting very close objects). The adapter has a dual focus. It is best used for crop cameras, perfect for Canon 40mm 2.8 lens, but it works with a full frame. There is no vignetting on a full frame with a focal length of 55-60 mm and on a crop of 1.6 and 1.5 with a focal length of 40 mm. On crop 2 (micro 4/3, 16 mm sensor) there is no vignetting at the focal length of 25-30 mm. The values shown are for fixed lenses. The values vary for zoom lenses. It is desirable that the diameter of the front lens of the taking lens is less than 70 mm. It is necessary to use very clear and sharp lenses - anamorphic adapter greatly reduces the depth of field (harder to focus), slightly blurs the image, blurs at the edges. Maximum sharpness is achieved at a distance of 10-20 meters, when the focus is from 20 mm to 80 mm. At a distance closer than 10 m, you must use diopters +0.3/+0.5/+1. The adapter has a clamping ring (clamp) included.