6D Helmets - Six Degrees of Freedom. In engineering terms, refers to the ability to move 3 dimensionally in space about the Cartesian coordinate system of X,Y and Z, including rotation about each axis. Now take this idea and incorporate it into a helmet. 6D Helmets are taking the regular helmets of today and completely reinventing them in attempt to truly develop the market. The ATR-1 is one of the most advanced helmets out today, meaning you can be completely at ease knowing you are completely safe.