# Shimano has raised the bar to a new level of performance with the development of a hollow outer chainring, giving vast improvements in rigidity and increased weight savings
# The hollow outer chainring has essentially removed outer chainring flex, hugely improving shift performance making it precise even under high load
# These industry leading HollowTech II cold forged hollow crank arms have been evolved to increase rigidity, reduce weight, and improve strength
# The teeth have been developed to work only in conjunction with the CN7900 chain for improved contact providing more efficiency and improved power transfer
# There is a wide range of chainring ratios and crank arm lengths available enabling customisation for all riders and racing disciplines
# HollowTech II integrated bottom bracket design uses a wider bearing placement and larger axle diameter for increased stiffness and efficiency
# Bottom bracket seal design has a minimal bearing interface gives superbly smooth rolling and increased durability
# Weight including bottom bracket 725 grams