Your stem has to resist flexing during sprints and accelerations, clamp securely to the fork and handlebar, and support your weight over significant impacts. It;s a difficult job, but the Service Course® stem is still able to combine strength, stiffness and reliability at a weight of 130 grams (100 mm length). The Service Course has high-strength, 3D-forged construction, 7075 series aluminum and stainless steel bolts to deliver an exceptional strength-to-weight ratio while allowing for smooth lines to complement the aesthetics of modern frames. We make our Service Course stems in seven lengths (70 mm to 130 mm in 10 mm increments) and two angles ( /- 6 degrees and /- 17 degrees) to meet any rider's fitting needs. We use TORX® heads on all bolts for precision torque readings and ease of adjustment. http://zipp.com/stems/service-course-stem/#
