Vintage/Leather XS S M L XL
shell 1 54 cm 55 cm
shell 2 56/57 cm
shell 3 58 cm 59/60 cm

 

Vintage (older models) XS S M1 M2 L XL
small shell 54 cm 55 cm 56-57 cm
normal shell 57-58 cm 59 cm 60 cm

 

Full face (Racer, Rocket, Seventyfive, A.S.R.) XS S M L XL XXL
small shell 53/54 cm 55/56 cm 57/58 cm
normal shell 59/60 cm 61/62 cm 63 cm