Taking many features from pro-level equipment, this 2-piece cap-free design Tiagra chainset offers unbeatable performance. Features: 2-piece cap-free design is quick and easy to install whilst being lighter and stiffer than a traditional crank/ bottom bracket assembly SG-X chainrings feature strategically placed chain pick-up pins and tooth profiles to ensure fast and positive shifting Designed to work with HollowTech II type bottom bracket cups Compatible with 10-speed HG-X chains Anodized aluminium crank arms Lightweight aluminium chainrings 4 arm, 110 mm bolt circle diameter Optimum power transfer motivates riders to pedal further and faster Optimal balance between stiffness and lightweight Reinforced 4-arm construction 110 PCD Optimized gear shape for HG-X chain Gear combination: 50-34T, 52-36T, 48-34TCrank arm length: 165, 170, 172.5, 175 Does not include a bottom bracket Genuine, brand new, boxed Shimano product - Biketart are an official UK Shimano stockist.