Taking many features from pro-level equipment, this 2-piece cap-free design Tiagra chainset offers unbeatable performance 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