Each Arai is a hand-made state-of-the-art item of safety equipment. An Arai RX-7 Corsair, for instance, takes 18 hours of skilled craftsmanship to produce. Its shell is made from SNS (Structural Net Composite) and incorporates a structural net reinforcing material embedded between the layers of Super Complex Laminate, and this is what gives the outer shell its strengt and energy absoption capability - without a weight penalty. The interior Hybrid Multiple Density Foam EPS line is of multiple densities, manufactured in one piece.
Crucially, Arai use five different sizes of outer sell, from XXXS to XXXL, with specifcally shaped inner shells for Europe, Asia and the USA - this is because head shapes differ continent to continent. Arai has spend the best part of 20 years fiting helmets to heads and the fit of each Arai is second to none for a reason; it's been designed that way.
Helmets exist for one reason alone - to reduce the amount of impact energy transmitted to the head in the event of an accident. The outer shell of the helmet absorbs the initial impact, dissipating it through the inner shell which then absorbs a great deal of both energy and inertia, effectively cushioning the brains decceleration.
All of Arai's helmets exceed greatly all of the testing standards througout the world. In Europe ECE22.05 is the standard to which all helmets sold must meet. But Arai sets high demands for its own helmets - much higher than ECE22.05. For example, the EVE norm accepts one single impact test on 5 areas of the helmet. Arai tests each helmet with no less than four successive impacts on nine places. The reason for this is simple; practice shows that a helmet, during and accident, often gets hit on the same place several times wen it reaches the road surface. So isn't it obvious to test the helmet more than once?
An example of this in action if MotoGP ride Sinya Nakano's high speed crash at Mugello in the 2004 season. His helme suffered repeated impacts from 200mph to standstill, and he walked away from that accident. His Arai took a heavy battering, but protected his head securely during the fastest crash in GP history.
Also, the ECE test does not require a penetraton test, which Arai insists upon. This is an important factor for road use, where all sorts of potential hazards can exist during an accident.
Arai has been protecting racers' and riders' heads for well over two decades, in the process turning the art of making crash helmets into a science. There is no testing standard in the world to compared with Arai's own and this fact, added to the sheer quality of materials and attention to even the smalled details ofound in every Arai helmet, is what makes each one so special.