The HiViz Magni-Hunter Magnetic Shotgun Sight features innovative magnetic attachment technology with cross-eye dominant correcting technology for improved accuracy and faster target acquisition.HiViz Magni-Hunter Magnetic Shotgun Sight (Model MGH2007-I)Fits shotgun ribs from .230" to .330" (15/64" to 21/64") (5.8mm to 8.3mm)Magnetic attachment system for secure tool-free installationCross-eye dominant correcting technologyIncludes two Green and two Red replaceable LitePipesFront sight only round shape designNarrow model for streamlined profilePerfect for hunters and sport shooters seeking quick sight acquisition and enhanced accuracy on shotguns with standard rib widths. The magnetic system allows for easy installation and removal without gunsmithing.