The Profile Helm MTB stem is for Downhill, Freeride, and Enduro applications. A. For standard 31.8mm/1.25 inch Bar Clamp and 1-1/8 steer tube. B. For oversized 35.0mm/1.375 inch Bar Clamp and 1-1/8 steer tube. 0 degree rise with moto-clamp front bolts (top two bolts fully tighten, bottom bolts to adjust clamp pressure). Made from fully CNC machined, 7075 Billet Aluminum. Stem body machined with radius and chamfered edges for a smooth finish. Anodized colors with laser etched graphics Colors: Black, Silver, Matte Black, Red, Blue, Gold, Green, Aqua, and Purple, and special wraps. Sizes/weights: 40mm (152g), 50mm (172g), and 60mm (198g)