The Hiviz M200, part of the M-Series, offers an adaptable magnetic sight to serve your needs. Engineered with a convenient snap-on magnetic base, it provides three color options - green, red, and the distinct Hiviz two-toned LitePipe. The Ultra Narrow variant of the M-Series model is designed to fit ribs ranging from .171\" to .265\" (11/64\" to 17/64\") or equivalently from 4.2mm to 6.7mm. Additionally, the Narrow version of this M-Series model can accommodate ribs from .218\" to .328\" (7/32\"-5/16\") translating to 5.5mm to 8.3mm. Finally, the Wide M-Series model is intended for those requiring larger sizes, fitting ribs from .328\" to .437\" (21/64\"-7/16\") or in metric measurements, from 8.3mm to 11.1mm.