Neewer 22mm Eyecup Eye Cup Eyepiece for Canon EOS 3/5/33/55/50E/50D; Olympus E-300/330/400/410/500/510 It makes the viewfinder readout easy to see even on a bright and sunny day. The plastic piece slips onto the eyepiece of your camera. Prevent eyeglass lenses from getting scratched. Prevent unwanted light from effecting your judgment of the image you are producing. Make shooting more comfortable.