Helmet part bontrager standard boa fit system short length

Genuine replacement Boa® system for Bontrager helmets; Compatible with Bontrager Boa-equipped helmets, except Velocis MIPS and WaveCel models; Can also be used to upgrade your Bontrager helmet equipped with the Headmaster system by exchanging it for the Boa system; Fit system long designed for size M and L helmets; Short adjustment system designed to optimize the fit of size S helmets;