• With several years of development and working closely with professional teams you can expect extreme accuracy from Shimano's first fully integrated power meter HollowTech II 12-speed Dura-Ace chainset
• Accurately calibrated strain gauges are integrated inside both left and right crank arms, this provides a stable measurement system through rotation from both sides for extremely precise data
• +/-2% accuracy of strain gauge measured power
• Bluetooth and ANT+ with wireless firmware update and data acquisition system
• Easily rechargeable integrated battery with fully waterproof reliable electric system
• 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 evolved to increase rigidity, reduce weight, and improve strength
• The teeth have been developed to work only in conjunction with the 12-speed chains 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

All UK Mainland Bike Deliveries Over £999 - Free Bike orders are sent via TNT/FedEx with estimated delivery within 1 working day after quoted dispatch time (For Scottish Highlands, Northern Ireland, Isle of Man and the Channel Islands deliveries please allow an additional 1-4 working days).Bike orders under £999 and eBikes will incur a £25 delivery fee.

Free Delivery On Orders Over £199.99 - When you spend more than £199.99 at 99 Bikes deliveries to a UK mainland address will be free (excludes bikes & large items).Certain regions and territories of the UK will incur additional charges, details of which can be found on our delivery page.

Click & Collect Orders -Please be aware Click & Collect orders may take some time to fulfil. We advise not to travel to your chosen store until you have been notified that your order is ready for collection.

At 99 Bikes our priority is to ensure that you are highly satisfied with your purchase. In the unlikely event that you aren't, we offer a 30 day online return policy* in which you can receive a full refund. Any item including bikes (with the exception of food) can be returned to us for any reason provided it is received by us in an unused and resalable condition in or with its original packaging which must be undamaged.

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