Alpinestars Hydro Sport Boots Microfiber upper. PU shin plate with air intakes provides ventilation. -- Dual density lateral and medial ankle cups with PU ankle slider. External PU heel counter. Internal toe counter. Injected high modulus polyamide midsole contours to the foot and features a high modulus plastic shank reinforcement. Instep and Achilles flex zones offer superior comfort. Waterproof and breathable Drystar lining. Rear reflective insert for improved visibility. Removable anatomic footbed and multi-density EVA padding. Alpinestars exclusive vulcanized rubber compound with slim sole profile. Large adjustable Velcro strap with an inner zip for secure closure and fit. CE certified.