To ensure your customers purchase the correct sized helmet, you need to measure
the crown of their head. With a tape measure or piece of string, measure around
the head, just above the ears in centimetres. Then refer to the information below to
ensure they buy correctly. Helmets should be a snug, secure fit and may be a little
tighter than the worn one they are used to. The fit of new helmets will relax a little.
The adult
sizes for the Rapido, H Force , GEM and Onyx III correspond as Below
XS = 52-53cm
S = 54-55cm
M = 56-57cm
L = 58-59cm
XL = 60-61cm
XXL = 62-63cm