The ST-1 Waterproof Jacket is designed for riders who need consistent comfort and weather protection for long-distance road touring and changing conditions. A fixed waterproof membrane provides dependable wet-weather performance while maintaining breathability, and front chest vents increase airflow across a larger surface area to help regulate temperature while riding. The jacket uses a comfort-focused touring fit with pre-curved arms and ergonomic elbows to support natural movement and reduce fatigue on extended rides. A modern shoulder design with Alpinestars branding gives the jacket an adventure touring–inspired look suited for both daily use and travel.

The jacket includes a detachable thermal liner with 80g insulation in the torso and sleeves, secured with snap button connections and easily removed as conditions change. When not in use, the liner can be stored in the large lower back cargo pocket. Storage includes expandable front cargo pockets, a zippered chest pocket, inner mesh pockets including one waterproof pocket, and a rear cargo pocket for carrying essentials. Adjustment points at the biceps, collar, cuffs, and waist allow riders to fine-tune the fit, while an extended rear cut improves coverage in the riding position. Tech-Air® Ready construction, CE Level 1 Nucleon Flex Plus shoulder and elbow armor, and full CE certification deliver trusted impact protection, and a pant connection zipper helps prevent wind ingress when paired with the ST-1 Waterproof Pants.