Shimano 105 5750 compact 10sp chainsetlightweight hollowtech ii 105 10 speed chainset please note bottom bracket is not included features innovative hollowtech forged and anodised aluminium crank arms utilise a hollow design that minimises flex and keeps the weight low the chainring teeth have been developed to work in conjunction with the cn 5701 chains for increased contact to provide greater efficiency and improved power transfer hollowtech ii allows the bottom bracket bearings to be spaced