1. The eyecup works as a cushioning around the camera's eyepiece which provides a protection for the camera's eyepiece.
2. No matter you wear eyeglass or not The hollow rubber of the eyecup is comfortable for your eyelid contact and your glasses.
3. Plastic with rubber it impress you a comfortable feeling following a pleasant experience.
4. Compatible with Canon 1DS Mark III / 1DS Mark IV / 7D / 5D Mark III.