Left-Side PRECISION Powermeter - Ride Ready

Non-Drive Side Precision Powermeter

Ride Ready
$334.99 USD

Used to pace attacks up the Alpe D’Huez in the Tour de France and to hammer on the Queen K during the Ironman World Championships, the PRECISION Powermeter delivers accuracy and reliability when you need it most. Through our patented 3D Strain Gauge technology, you can be assured that the data you depend on will lead you to your own Yellow Jersey. Packaged into a durable lightweight design and compatible with ANT+ and Bluetooth Smart headunits, PRECISION will help you train harder and smarter.


How Does It Work?

A ride ready PRECISION pod is already preinstalled on a brand-new Shimano crank arm at our factory. The moment you order, our fulfillment team will get it on its way to you, and you should be able to ride with power as soon as it arrives.

Important: You need to use the frame clearance guides to ensure there is space between your crank and frame for the PRECISION pods.

In The Box

Once your ride-ready PRECISION Powermeter arrives, it just needs to be installed on your bike using the standard Shimano crank installation process. Connect a headunit or computer, and you can start riding with power!

Tip: If you’re unsure, a bike shop would be happy to aid you in the installation process.

Warranty & Durability

Ridden through rain storms at Strade Bianche, mud filled cross country mountain bike races, and even tested amidst the salt spray of the ocean on Oracle Team USA’s America’s Cup competitors, you can be assured that your 4iiii power meter will be as tough as you are and is backed with an industry leading 3-year warranty. All 4iiii power meters are IPX7-rated for water immersion up to one meter and backed with an industry-leading 3-year warranty.

  1. 4iiii Warranty Policy


  • Light Weight

    At only 9 grams the Precision 3 Powermeter weighs about the same as a sip from your water bottle. Our goal is to help you get faster, not to slow you down.

  • Battery Life

    With over 100 hours of battery life, you won’t have to worry about frequent changes.

  • Accuracy in 3D

    Not everyone has the perfect pedal stroke. With +/- 1% accuracy, 4iiii is the only crank-based power meter to use 3 strain gauges to measure all forces in your pedal stroke.

  • 3 Year Warranty

    A lot can happen in 3 years. You probably won’t need to use it, but it’s reassuring to know that all 4iiii power meters are backed by an industry leading 3-year warranty.


Specification Value
Module Weight 9g (0.6oz)
Power Range 0 - 4,000W
Cadence Range 30 - 150RPM
Communication Protocols ANT+, Bluetooth
Operating Temperature 0 - 50°C (32 - 122°F)
Storage Temperature -20 - 50°C (4 - 122°F)
Battery Type CR2032 lithium ion coin cell
Battery Life 100+ hrs
Waterproof Rating IPx7, IPx5
Length 37.7mm (1.5in)
Width 27.6mm (1.1in)
Depth 7.5mm (0.3in)


A 4iiii PRECISION power meter is available ready to ride on any of the crankset configurations listed below. If your desired crankset isn't listed, we may have other products that are compatible.

  • Shimano 105 FC-R7000
  • Shimano Ultegra FC-R8000
  • Shimano Dura-Ace FC-R9100
  • Shimano GRX FC-RX810
  • Shimano XT FC-M8100
  • Shimano XTR FC-M9100


If the weather or climate make riding outdoors tough, your 4iiii power meter can be used with all popular indoor-training apps, such as Zwift, TrainerRoad, Wahoo SYSTM, Rouvy, and more. Simply use your favourite app’s connection procedure over ANT+ or Bluetooth Smart, put your bike on a trainer, and get riding!

  1. Indoor Training


  1. Quickstart Guide
  2. Clearance Guide (Letter)
  3. Clearance Guide (A4)
  4. iOS App
  5. Android App

Customer Reviews

Based on 36 reviews
Petr Brynda
Disappointed with the product

I was very much looking forward to the arrival of the power meter. After less than 2000 km of using it, I have to say that I am very disappointed. The battery definitely won't last 100+ hours. During that time, I have already changed 4 batteries, each after approx. 18 hours. I use Powermetter with Garmin Edge 830 and the connection is very unstable and drops out of 20-30% of the recording. The measurement is therefore unusable. I've already tried a factory reset. It looks even with a brand new battery. At the same time, the speed sensor located on the rear wheel has no problem.

Hi Petr,

Check your inbox. Our customer service team will be in touch shortly.

The 4iiii Team

Bryan Bergstedt
4iiii Precision Power Left Side Factory Install

Just ordered a third Precision power meter form 4iiii. The first two failed in an identical manner outside of warranty with ~3 years use each. I only hope that this new one will last a little longer. Thankfully, 4iiii offered a discounted price this time around due to the failure. My recent new purchase started out uneventful, like both of my previous purchases with overnight FedEx shipping (my crank) to 4iiii. I was not given any time frame for installation so after 1.5 weeks without any update I contacted 4iiii to see if they could provide an apprx time frame for installation. They told me their current backlog was putting installations out two weeks. In the past it was more like 2 days, but I suppose that's the way things go these days? Sure enough, at 16 days after receipt by 4iiii my install was complete. A couple of days after that 4iiii started shipping process back to me. I'm without a bike throughout this process so the timing isn't exactly what I wanted, but logistics are just different these days so I know I've got no choice but to roll with it. Here's the hitch... 4iiii sent my crank back via Canada Post 14 days??? Total time without a bike... Five Weeks! After two product failures and sloooow shipping decisions on my current order, I'll look for other options next time I'm in the market for a power meter. Not sure what happened to these guys, but this time around is like night and day compared my past experiences.

Great value and training tool

I live in Asia, I ordered online and used Fed Ex shipping. It was just a little more than regular shipping and I received my power meter after 1 week. It was great. The power meter was super easy to install. I chosen 105 because there was very little difference between 105 and Ultegra left crank, what a great value. I purchased another one for my TT bike also because it is so much easy to train with precision power meter now.

Chris C.

I own three of these now…..one on each of my Cannondales! Have had two of them for three years now and have had zero issues!

Anthony Bush
Excellent value, great support

I've had my power meter since early 2017. I had some early issues, but support was great and I got everything resolved. It's been five years and no issues since (I only ride 3000-6000 miles per year, and ~8000 miles total on the bike I installed this on). This left arm power meter has provided excellent value, and I'm thinking of getting more for my other bikes. It's a lot more fun riding with power as I find myself playing a game to push harder when I should push harder, and back off more when I should rest (active recovery). I also track heart rate (since 2015) and it lags too much and varies with temperature (I ride ~35-110F° in Austin, TX). I've done some 4-week training plans as well, and the power meter is essential in completing the workouts correctly. Your legs won't regret it!