Alpinestars Supertech R Boot Almost every component of the Supertech R Boot, Alpinestars definitive racing boot as worn by a roster of champions past and present, has undergone a rigorous program of upgrades to sharpen its performance features even further. Featuring innovations derived using feedback from Alpinestars involvement in top flight racing, key elements include a newly redesigned front flex area, a redesigned rear bellow, a redesigned top gaiter, a new shifter and shin plate, a new shin slider and a new inner bootie, all of which enhance the comfort, protection and the performance of this boot to a new class-leading high. Features: Main upper material constructed using microfiber for optimum abrasion resistance and flexibility  New front flex area for improved impact abrasion New front flex area increases ventilation and airflow Redesigned rear bellow in stretch microfiber for improved natural front and back movement  Redesigned top gaiter in microfiber material with TPU over injection New synthetic microfiber panel on medial side for enhanced abrasion resistance and improved feeling New TPU shifter for increased protection on lower medial side New TPU shin plate has been redesigned for greater impact absorption performance New replaceable shin slider for additional abrasion resistance  New TPU stretch panel design with zip for an easier entry and exit and a closer fit Hook and loop closure secures the puller zip remains in position Micro adjustable ratchet closure on top of boot for an optimized fit  Replaceable co-injected TPU/aluminum toe slider with an easy screw system Replaceable heel plate slider offers increased sliding performance and protection in the case of crash  Sole constructed using a lightweight rubber compound for excellent grip on the pegs Separate bio-mechanical inner bootie made by 3D mesh material for greater structure Inner bootie is equipped with a new external toe area with a soft TPU reinforcement Bootie provides impact protection and additional ankle padding for greater protection, stability and cushioning Meets CE CE EN13634:2017 standards