The C100 Z-Finder Pro is an optical viewfinder, specifically designed to attach to the Canon C100 cinema camera LCD. This Z-Finder will magnify the LCD screen by 1.8x and has a diopter for specific focus tuning. It cuts out any extraneous light and offers an initial point of stability by pressing your eye against the large eyecup. The C100 Z-finder Pro comes with a 40mm diameter Zacuto optical lens, anti-fog coated protective covers, and all necessary additional accessories for the Canon C100. The diopter allows you to dial in the focus to match your eye. If you need extra focal points you can use the included Z-Finder Extender Frames. These are semi-permanent stackable frames that attach to the body of the Z-Finder Pro and extend the Z-Finder glass further away from the LCD screen for people who are farsighted.