Optimized for wide-aperture lenses, specifically in the f/1.8 - 2.8 range, this Eh-S Super Precision Matte Focusing Screen from Canon is designed to obtain sharp points of focus with their EOS 7D Mark II DSLR Camera. It's especially well-suited to situations in which you're manually focusing in dim light with fast lenses, and its fine microlens structure allows for high performance in various scenes.
Areas that are slightly out of focus will appear more so, making it easier to tell when focus is right-on. With lenses that have a maximum aperture smaller than f/2.8, a Super Precision Matte screen will appear dark and grainy. Like all Canon focusing screens, this one is compatible with EOS autofocus systems.
The screen serves as a replacement for the standard screen originally installed. Use the supplied installation tool to place it into the retaining frame inside the camera. Focusing screens are extremely delicate and should be handled with great care. Always use the special installation tool provided. Never touch the screen with your fingers or hold it in your hand, and always keep it away from dirty or abrasive surfaces, as dirt and smudges will be difficult to remove and scratches will be permanent. Dust can be removed with a manual air blower.