Just received 2 new eyecups and decided to install them. Here are some pictures of installing one for those thinking of buying a DK-19 eyecup. Close viewfinder shutter. Unscrew original eyepiece counter clockwise. Original eyepiece and new DK-19 from package. Remove metal ring from DK-19. Flip original eyepiece over so threads are up. Remove original rubber ring from eyepiece. Start to instal original eyepiece into new DK-19 eyecup. Make sure threads are up. Eyepiece fully installed in new DK-19 eyecup. Install metal retaining ring over new eyecup and eyepiece. Clean the glass on the eyepiece before installing. Screw eyepiece with DK-19 eyecup open onto camera clockwise until slightly tight. Open viewfinder shutter before collapsing new DK-19 eyecup. New eyecup opens and collapses with just a push around the outside.