4iiii Crank arm left Precision 3+ Shimano GRX RX810 RX820 Power meter

The 4iiii PRECISION 3+ Powermeter is the ultimate combination of accuracy, durability, and lightweight design. Whether you are a Tour de France pro, a Mountain Bike World Champion, Ironman triathlete, a Zwift racer, or a cyclist simply looking to add the structure of data to your training, this crank-based power meter provides the consistent data you need to unlock your potential.

Engineered to be the best affordable power meter on the market, the PRECISION 3+ features Apple Find My technology, allowing you to track your bike’s location with ease. With +/-1% accuracy, automatic terrain selection, and an industry-leading 800-hour battery life, it is built to handle everything from rough terrain and gravel to high RPM sprints.

This Ride Ready unit comes pre-installed on a brand-new Shimano crank arm, simply swap your left-side crank and start training. Backed by our 3-year warranty and an IPX7 waterproof rating, the PRECISION 3+ is your dedicated performance tool for years to come.

BONUS: FREE TRAINING WITH JOIN CYCLING. Every 4iiii power meter purchase includes 8 weeks of free premium training on the JOIN Cycling App. Whether you’re prepping for a local Gran Fondo or aiming for a new FTP personal best, JOIN provides flexible, adaptive training plans that sync perfectly with your new PRECISION 3+ data.