The HoodMAG 3.0 is designed to fit where the original HoodLoupe 3.0 eyecup was installed. Remove your original HoodLoupe rubber eyecup by pulling the low profile eyecup up and off of your HoodLoupe. Mount the HoodMAG by pushing it over viewing end of HoodLoupe. HoodMAG has a tighter fit than the original eyecup and will stay in place once mounted.
