To select the suitable size of helmets to fit the head is very important. Since the incorrect dimension could not protect our brain well from impaction, so don’t make mistake to buy a helmet which is not fit our head. If you are doubt which sizes of helmets will fit our head, first we can measure the head at maximum portion (usually it is up eyebrow 1mm), then buy the helmet according to this measurements. As the helmets always have three sizes: size L, size M and size S, We may only buy the helmets with relatively suitable size, and adjust the size by the fit system to reach the best fit.
When try to wear the helmet, turn it from one side to other side, from front to back, to check whether our brain is in comfortable felling or not. If too loose or too tight will require the further adjustment or change the other one.