Explore Scientific 3" 0,7x Reducer/corrector Reduces the focal length by the factor 0,7x (for f/8) and 0,8x (for f/10) respectively. The reducer/corrector not only reduces the focal length but also flattens the field. Although originally developed for the Explore Scientific ED-APOs 127mm and 152mm, the reducer can be used with many systems. Comes with 3" barrel and T2- adaptor. Free aperture 65mm, so that it can be used even with cameras that have a large sensor - if the telescope allows for this.