Shimano 105 5800 11 speed double chainset silverthe shimano 105 5800 chainset features a four arm hollowtech ii design similar to that of current ultegra and dura ace models its stiffer and lighter than its predecessor and shimano has reinforced construction around the chainring area to further improve the stiffness to weight ratio featureslightweight hollowtech ii 105 11 speed chainsetinnovative hollowtech forged and anodised aluminium crank arms utilise a hollow design that minimises flex a