CRANKBROTHERs Crank Brothers Cobalt 11 Bike Stem CARBON FIBER- The Cobalt 11 stem is an all carbon fiber stem and the lightest XC stem on the market. SINGLE PIECE CONSTRUCTION- Features the high modules carbon XC system with torx bolts for steer tube and handlebar. SPECIFICATIONS- Diameter: 31.8mm, Weight: 125g, Length:100mm NOT COMPATIBLE FOR BARS WITH MORE THAN 15MM RISE