The Tephra Max's three-layer design features Flexicore technology for maximum shock absorption, a Shokbloker outer, and a Geldform liner for super comfprt. It's CE approved and certified. The Tephra Max convertible incorporates the same feature and technologies as the Tephra Max - Shokbloker, Flexicore, Geldorm, Boil&Bite, Airthru, and Slipsafe pads- plus a helmet strap you can use to attach the mouthguard to your helmet. The strap is fully removable, which means you can choose to wear your helmet with or without it.