Alpinestars Fluid Narin Pants Black/White 40 The Fluid Pants offer optimized levels of comfort and performance in the riding position, thanks to their lightweight chassis, lower waist stretch panels and pre-curved leg design. Developed and tested on some of the toughest terrains around the globe, the sport fit Fluid Pants are ideal for many forms of off-road riding. 3D pattern construction for enhanced rider comfort and unparalleled freedom of movement. High performance synthetic leather on knees for high levels of heat resistance, grip and comfort. Ratchet closure for a secure, personalized fit. 600D poly-fabric main chassis construction. Stretch fabric panels on crotch, knees and rear waist for enhanced rider comfort. Mesh lining for enhanced rider comfort.