The LCDVF Viewfinder for Canon EOS 5D Mark III and 1D X DSLR Cameras is an optical viewfinder used to shoot either photos or videos with better camera control and view of 3.2" LCDs. It is an essential accessory that enables photographers to take advantage of the video features of DSLR cameras with larger 3.2" LCD displays.
At the heart of the LCDVF3C is an achromatic lens pair that consists of two optical components vacuum-cemented together to form a lens which is computer optimized to correct for chromatic aberrations. Its magnetic interface allows rapid mounting and removal without any wear and tear on the camera. All you need to do is apply the adhesive-covered thin metal frame to your camera body and from then on, it's a simple click-on / click-off solution to attach and remove the viewfinder.