Perhaps most importantly

Upgrade your cycling game with the SRAM Cassette XG-1391 13 speed

Engineered with ProTection puncture resistance and a multi-layer carcass

Featuring a 13-tooth upper pulley wheel and a 19-tooth lower pulley wheel to provide absolute optimisation of the rear derailleur

and aesthetic appeal

shimano chainring 53t dura ace r9100 Product Type_Rain Jacket Perhaps most importantlyThe Shimano Dura Ace FC R9200 chainring uses hollow forged technology to provide a significant weight loss while giving increased rigidity. This guarantees the optimum power transfer. SHIMANO 2 12 speed chainring for Dura Ace FC R9200 crankset and Dura Ace FC R9200 P cranks with powermeter. While the inner chainring is made of anodised aluminium, the outer chainring has been hollow formed (Hollowglide) from anodised aluminium and carbon fibre