Alpinestars Pro-Dura Pants are derived from motocross and designed to provide high levels of durability. Dedicated off-road riding fit. Breathable, stretchy, yet strong Stretchnet, lower leg inserts have been used on the backs of the legs for fit and freedom of movement. Pre-curved knees and waistline, allow the pants to easily fit over knee protectors and knee braces. Constructed from four-way stretch ripstop main chassis, with high-resistance ripstop material used on the seat, thighs, and knees for added durability. Comfort stretch corduroy in the crotch and behind the knees. Opening vents on the sides of the thighs for airflow and breathability. Secure and quick SX2 auto-lock, magnetic buckle, and waist adjustment system, offer a customized waist closure for a personalized fit. Durable, washable goat leather used on inner knees to provide great connection and feel with the bike.