MC CONVERTER K-1 2.x - Soviet Arsenal converter production plant. Converter is suitable for all lenses with a landing threaded M42 x 1 / 45.5. K-1 increases the focal length by 2 times, while the number of F is also doubled, respectively, lens aperture is reduced by 4 times (2 stops). Also, K-1 device supports blinking aperture. Asking questions and watch my other lots have a large selection of lenses.  Shipping We ship via registered mail through 12-36 hours after payment. Usually it takes about 10-14 days for a package to arrive to Europe, 14 days to USA, Canada  Return Policy  I always try to describe item as good as possible, to check everything out for you could be satisfied with your purchase, but nobody is perfect and me too.  If you have questions after receiving the goods please ask them to me