The Kask protone uses in-mold construction. This means that the polycarbonate shell is bonded to an eps foam body. This is then secured over a frame, which allows the shell to absorb impact while keeping the structural integrity of the helmet. The protone is secured with Kask octo fit cradle that adjusts to personalize the fit. The eco chinstrap is antibacterial. Not merely a shell to keep your head intact, the protone is also an essential aerodynamic accessory. The helmet's interior padding is sewn from CoolMax, which helps to pull moisture from your head to keep you cool. To further assist with cooling, Kask placed the protone in a wind tunnel and added large front vents and rear ports. The open design allows optimal airflow and doesn't sacrifice aerodynamics.