This is an Aprilia Head Light Rim for the Ducati Bevel 860 GT and 900  SS  models.  For 170 mm Aprilia 35964 optic units but also the CEV type 168 unit fits in this rim. Also for  other Italian bikes of the seventies like the Moto Guzzi V7 850 T.  Very nice state as this is a NOS part, see pictures.

Ducati roundcase, Imola, Greenframe, SS, SD, GTS, MHR, SSD, Darmah, squarecase, S2, sport, supersport, Borrani, Ceriani, Scarab, Lockheed, Marzocchi, Brembo, monza , diana, mach, mach1, dm250, dm350, dm160, 160, 450, dm450, desmo, desmodromica, elite, elite 200, brembo, 900SD, Mark 3 , mark 2, CEV, 750, 750GT, 860GT, 900GT, MV Agusta 750 America GT SS