Heavy Duty screw in type rectangular mirror fits Moto Guzzi models with threaded mirror mounting holes. Fits left or right side. Spring loaded pivot helps the mirror move when impacted, rather than bending or breaking off. Stem is a thick 12.5mm, mirror head is large at 3 x 5.5 inches, stem is long at 7 inches. Threads into 10mm x 1.25 hole.