Aprilia NOS #4521 tail light lens that fits lots of Italian bikes of the 1950's and 60's. The lens measures 85mm OD and is smaller that the #127 lens and not interchangeable.
Lenses are original Aprilia New Old Stock and two piece not one piece like the modern reproduction lenses.
NOTE: Lenses were made in the 1960's and have some shelf ware. !! Very Limited Supply !!