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4iiiiShimano Ultegra R8000 Precision Left-Side Power Meter

4iiiiShimano Ultegra R8000 Precision Left-Side Power Meter


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5 out of 5 stars
1 Review

Shimano Ultegra R8000 Precision Left-Side Power Meter

You're a "numbers guy." It began in high school when your stats teacher handed out assignments, and continued into adulthood when your boss asked you to review the annual report. Even when you hop in the saddle to train, your mind is driven onward by the data that surrounds you. And that's why you ride with the 4iii Shimano Ultegra R8000 Precision Left-Side Power Meter — so you can push your limits knowing data from every pedal stroke is measured for optimal performance. And all you had to do was install the Precision power meter crank arm to collect tangible and reliable numbers on your quest to improve your ride.

The secret behind this crank arm is the 4iii power meter pod affixed to the side of the arm, which takes what was originally a standard Ultegra R8000 crank arm to the next level with readings accurate to +/− 1.0%. The coincel battery offers 100 hours of life, giving you plenty of time to gather and scrutinize data for rides to come before a recharge is required.

For those that obsess over every ounce, the Precision is one of the lightest power meters on the market, adding only 9 grams to the crank arm in exchange for precise data that only a power meter can provide. When the time comes to look over the facts and figures, simply connect the Precision to the 4iii app on your phone via ANT+ or Bluetooth SMART for information at your fingertips.


  • Hollowtech II left side crank arm with built-in 4iii power meter
  • +/- 1.0% accuracy lets you collect training data with confidence
  • Accelerometer with gyroscope offers detailed cadence readings
  • 9g design is one of lightest crank arm-based meters on the market
  • 100 hours of battery life via replaceable CR2032 battery
  • Pair to the 4iii app with ANT+ and Bluetooth SMART to transfer data
  • Item #FII0003

Tech Specs

Hollowtech II
Dual-Channel ANT+, Bluetooth Smart,
Accuracy (+/-)
standard CR2032 coin cell battery
Operating Time
100+ hours
Claimed Weight
0.3oz (9g)
Manufacturer Warranty
3 years
road cycling

Overall Rating

5 based on 1 ratings

Review Summary

5 Stars - 1 reviews
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1 Stars - 0 reviews

Fits True To Size

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