POC's Ventral Spin Helmet is touted as the most aerodynamic, well-ventilated, and safest road helmet ever produced by the Swedish protection experts. Its name takes inspiration from the guiding scientific principle behind the helmet's design: the Venturi effect. This scientific principle states that by constricting airflow in a choke point, the air pressure subsequently drops as it gains velocity. POC's engineers used this guiding principle to maximize ventilation by sculpting massive airflow vents in the front, which channel air inside constricted channels over the top of your head, then out from large exhaust ports along the sharp, trailing rear. By speeding up the flow of air inside the helmet, the Venturi effect means you'll remain cool and comfortable as you ride at a blistering cadence, even in the summer heat. Not only that, but the sharp trailing edges of the helmet and large exhaust ports smoothly reattach airflow coming through the helmet with that moving over the top, subsequently minimizing turbulence off the rear end, which is critical in making an exceptionally aerodynamic helmet. POC decided to upgrade the Ventral Spin's protective properties with their newly introduced Spin rotational protection impact system. This minimizes the traumatic forces from crashing at an oblique angle by allowing the helmet to rotate independently around your noggin in the case of an angled crash. Spin pads placed inside the helmet are fixed in place, but exhibit a bit of movement, which gives the helmet a bit of shear in the case of a crash. These pads are made of a silicone-based material on the bottom for extra impact mitigation, lined with traditional foam on top for sweat-wicking comfort. Now, we generally take claims of watt-saving aerodynamics with a grain of salt, but POC makes an excellent case for employing well-known science into the making of their flagship road helmet, thereby increasing its streamlined efficiency while boosting comfort in the stifling h...