The shimano 105 5800 5034 11 speed double chainset is a lightweight 105 11 speed chainset that uses innovative hollowtech forged and anodised aluminium crank arms that utilise a hollow design that minimises flex and keeps the weight low the chainring teeth have been developed to work in conjunction with hg x 11 speed chains for increased contact to provide greater efficiency and improved power transfer the chainrings are lightweight anodised sg x aluminium for precise and smooth shifting hol