The alpinestars smx 6 v2 racing motorbike boots are packed with features specifications include new microfiber design on front rear bellow and rear calf plus tpu ankle brace protector to give more protection flexibility and stability durable hi tech microfiber upper construction offering superb levels of flexibility tpu lateral ankle brace protection provides biomechanical support between lateral top calfshin and ankle and offers improved structural integrity air vents on shin