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Union 21TW cycling computer
Union

Union 21TW cycling computer

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Features of Union 21TW

Product description of Union 21TW cycling computer

Description summary

Elevate your rides with the UNION 21TW cycling computer. This durable, weather-resistant device delivers precise real-time data on speed, distance, and time, helping you track progress and optimize performance. Integrated sensors for acceleration and cadence offer deeper insights into your cycling dynamics, enabling you to refine technique and power output. With its large, easy-to-read display, long battery life, and simple installation, the UNION 21TW is the perfect companion for cyclists aiming to conquer every ride

Conquer Every Ride with the UNION 21TW Cycling Computer

The UNION 21TW cycling computer is your ultimate companion for tracking and enhancing your cycling performance. Packed with essential features and a user-friendly design, this device empowers you to push your limits and achieve your cycling goals.

Effortlessly Monitor Your Progress:

Stay informed about your ride with real-time data displayed clearly on the large, easy-to-read screen. The UNION 21TW provides accurate measurements for:

* Speed: Track your current, average, and maximum speeds to monitor your progress and optimize your performance.
* Distance: Accurately measure your trip distance, total distance, and odometer readings for comprehensive ride analysis.
* Time: Keep track of your ride time, elapsed time, and clock to manage your training sessions effectively.

Unlock Enhanced Performance Insights:

Go beyond basic metrics and gain valuable insights into your cycling dynamics with the integrated sensors:

* Accelerometer: Measure your acceleration and deceleration forces to understand your power output and optimize your pedaling efficiency.
* Cadence Meter: Monitor your pedaling cadence (RPM) in real-time to improve your pedaling technique and find your optimal cadence zone.

Designed for the Dedicated Cyclist:

The UNION 21TW is built to withstand the demands of your rides:

* Durable and Weather-Resistant: Confidently ride in various weather conditions with the durable and weather-resistant construction.
* Long Battery Life: Enjoy extended rides without worrying about battery life, thanks to the long-lasting battery.
* Easy Installation: Set up the computer on your bike quickly and easily with the included mounting accessories.

Technical Specifications:

* Display: Large, easy-to-read LCD screen
* Connectivity: Wired sensor connection
* Water Resistance: IPX6
* Battery Life: Up to 40 hours

Take your cycling to the next level with the UNION 21TW cycling computer. Order yours today and experience the difference!

Specifications

Manual

Technical specifications of Union 21TW

  • Display Type

    LCD

  • Battery Life

    Up to 40 hours

  • Water Resistance Rating

    IPX6

  • Speed

    Yes

  • Distance

    Yes

  • Color

    Grey

  • Features

    Cadence meter

  • Features

    Speedometer

  • Features

    Accelerometer

  • Product Type

    Odometers

Features of Union 21TW

Color Grey

Color

Grey

Features Cadence meter

Features

Cadence meter

Speedometer

Speedometer

Accelerometer

Accelerometer

Product Type Odometers

Product Type

Odometers

Key differentiators

Durable, weather-resistant construction with an IPX6 water resistance rating

Integrated accelerometer and cadence meter for advanced performance analysis

Large, easy-to-read LCD display for clear data visibility

Long battery life of up to 40 hours for extended rides

Tracks key metrics including speed, distance, time, and odometer readings

Technology in Union 21TW cycling computer

Energy rating

Warnings

/ 5

1 Reviews

What our customers are saying about Union 21TW cycling computer

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The question has already been answered, thank you very much for trying to help another customer. We will count on you for future questions.

Include AI Generated questions and answers

2026-09-06

Generated by AI and verified

Union 21TW cycling computer

What kind of data can I track with the Union 21tw Cycling Computer?

Answer of Generated by AI and verified

The Union 21tw allows you to track essential ride data in real-time. It measures your speed, distance traveled, and ride time. It also includes an accelerometer and a cadence meter to provide deeper insights into your cycling dynamics, such as power output and pedaling efficiency.

* Generated by AI based on customer and product data

2026-09-06

Generated by AI and verified

Union 21TW cycling computer

How long does the battery last on the Union 21tw?

Answer of Generated by AI and verified

The Union 21tw Cycling Computer offers a battery life of up to 40 hours on a single charge, allowing for extended rides without the need for frequent recharging.

* Generated by AI based on customer and product data

2026-09-06

Generated by AI and verified

Union 21TW cycling computer

Is the Union 21tw cycling computer suitable for use in the rain?

Answer of Generated by AI and verified

Yes, this cycling computer is designed to be weather-resistant. It has an IPX6 water resistance rating, which means it can withstand heavy splashes and rain, allowing you to ride confidently in various weather conditions.

* Generated by AI based on customer and product data

2026-09-06

Generated by AI and verified

Union 21TW cycling computer

Is the Union 21tw Cycling Computer worth buying for a serious cyclist?

Answer of Generated by AI and verified

The Union 21tw Cycling Computer is designed for dedicated cyclists, offering real-time analytics and a user-friendly interface. Its durability and weather resistance make it a reliable choice for those looking to enhance their cycling performance.

* Generated by AI based on customer and product data

2026-09-06

Generated by AI and verified

Union 21TW cycling computer

What type of display does the Union 21tw have?

Answer of Generated by AI and verified

The Union 21tw is equipped with an LCD display, which is designed to be large and easy to read, ensuring you can clearly see your ride data at a glance.

* Generated by AI based on customer and product data

2026-09-06

Generated by AI and verified

Union 21TW cycling computer

Does the Union 21tw have GPS capabilities?

Answer of Generated by AI and verified

No, the Union 21tw Cycling Computer does not have built-in GPS functionality.

* Generated by AI based on customer and product data

2026-09-06

Generated by AI and verified

Union 21TW cycling computer

Does this bike computer include a cadence sensor?

Answer of Generated by AI and verified

Yes, the Union 21tw includes an integrated cadence sensor. This allows you to monitor your pedaling rate (RPM) in real-time to help improve your technique.

* Generated by AI based on customer and product data

2026-09-06

Generated by AI and verified

Union 21TW cycling computer

How does the Union 21tw connect to its sensors?

Answer of Generated by AI and verified

The Union 21tw uses a wired connection for its sensors. This ensures a stable and reliable data feed from the sensors to the main computer unit.

* Generated by AI based on customer and product data

2026-09-06

Generated by AI and verified

Union 21TW cycling computer

What is the water resistance rating of the Union 21tw Cycling Computer?

Answer of Generated by AI and verified

The Union 21tw Cycling Computer has an IPX6 water resistance rating, allowing it to withstand heavy rain and wet conditions.

* Generated by AI based on customer and product data

2026-09-06

Generated by AI and verified

Union 21TW cycling computer

Is this a good computer for tracking training progress?

Answer of Generated by AI and verified

Yes, the Union 21tw is a great tool for tracking your training. It provides real-time data on speed, distance, and time, along with an integrated cadence meter and accelerometer to help you analyze and refine your performance over time.

* Generated by AI based on customer and product data

2026-09-06

Generated by AI and verified

Union 21TW cycling computer

Is the Union 21tw suitable for long-distance cycling?

Answer of Generated by AI and verified

Yes, the Union 21tw is ideal for long-distance cycling due to its 40-hour battery life, ensuring it lasts through extended rides.

* Generated by AI based on customer and product data

2026-09-06

Generated by AI and verified

Union 21TW cycling computer

How does the Union 21tw compare to the Union 5 Functions Cycling Computer?

Answer of Generated by AI and verified

The Union 21tw offers advanced features like an accelerometer and cadence meter, which are not specified for the Union 5 Functions Cycling Computer. This makes the 21tw more suitable for cyclists seeking detailed performance insights.

* Generated by AI based on customer and product data

Ask a technical question about this product

Frequently bought together
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Use cases

Dedicated Training Rides 90% Fit

This computer is ideal for focused training sessions where performance metrics are key. The included cadence sensor allows you to monitor and optimize your pedaling efficiency, a crucial aspect of structured training.

Cadence meter,Speedometer,Odometers

All-Weather Commuting 90% Fit

With its IPX6 water resistance rating, the Union 21tw can withstand heavy rain, making it a reliable companion for daily commuters who ride in all conditions. The long battery life also means less frequent charging, perfect for consistent use.

IPX6 water resistance,Up to 40 hours battery life

Long-Distance Touring (Non-Navigational) 80% Fit

For cyclists on long tours who prioritize logging miles and ride time over map-based navigation, this device is a great fit. Its impressive battery life of up to 40 hours ensures it will last for multiple days of riding without needing a charge.

Up to 40 hours battery life,Distance tracking,Odometers

Fitness and Recreational Cycling 75% Fit

Riders focused on fitness and tracking basic ride statistics will find this computer highly effective. It reliably tracks essential data like speed and distance, providing the necessary feedback to monitor progress and stay motivated.

Speedometer,Distance tracking

GPS-Free Data Logging 100% Fit

This device is perfect for cyclists who want accurate ride data without GPS tracking, either for privacy reasons or to simplify their setup. The wired connection provides a stable and reliable data feed for speed, distance, and cadence directly from the bike's sensors.

gps_enabled: no,connectivity_type: wired,Cadence sensor

Best for

Best for Training

This computer provides essential training data, including a cadence sensor and speedometer, to help you analyze and optimize every ride.

Cadence sensor: Yes, Functions: Cadence meter, Speedometer

Ideal for All-Weather

With its high water resistance rating (IPX6) and long battery life, this device is built to withstand daily use in various conditions without frequent charging.

Water resistance rating: IPX6, Battery life: Up to 40 hours

Great for Tracking Fitness Goals

It tracks key metrics like speed and distance with a user-friendly interface, making it simple to keep tabs on your rides and stay motivated.

Functions: Speedometer, Odometers

Reliable for Long-Distance Rides

The impressive battery life of up to 40 hours ensures it will keep tracking your speed and distance on even the longest excursions.

Battery life: Up to 40 hours, Functions: Speedometer, Odometers

Benefits

FunctionalTrack Key Metrics for Performance Insights

This cycling computer provides comprehensive data to analyze and improve your performance. It tracks essential metrics including speed, distance, and pedaling cadence, offering a complete picture of your ride.

Functions: Accelerometer

Cadence meter

Speedometer

Odometers

Speed: Yes

Distance: Yes

Cadence sensor: Yes

FunctionalRide Confidently in Any Weather

Don't let the weather dictate your training schedule. With an IPX6 water resistance rating, this cycling computer is protected against powerful water jets, ensuring reliable performance in heavy rain and challenging conditions.

Water resistance: IPX6

Water resistance rating: IPX6

Ideal buyer profiles

Chris enjoys cycling for leisure and fitness, often taking rides on local paths and roads. He's not training for a race but wants to track his basic stats like speed and distance to see his progress and stay motivated.

The Union 21tw is an excellent match because it provides all the essential data Chris needs—speed, distance, and cadence—through a straightforward wired system. With its impressive battery life of up to 40 hours and a clear LCD display, it's a reliable, low-maintenance tool for tracking casual rides without the complexity of GPS or wireless pairing.

Competitive features

When choosing a cycling computer, it's helpful to see how different models stack up. This analysis focuses on the core functionalities and what sets each device apart for cyclists looking to track their performance.

Where it excels

The Union 21tw provides essential real-time data, including speed, distance, and time, on a large, easy-to-read display. It includes integrated sensors for both acceleration and cadence, offering deeper insights into your cycling dynamics to help refine technique and power output.

Consider alternatives if...

The provided data does not specify features such as GPS, map support, or connectivity options like Bluetooth or ANT+. Cyclists who require advanced navigation, heart rate monitoring, or wireless data syncing with third-party apps may need to evaluate other models that explicitly offer these capabilities.

Verdict

The Union 21tw Cycling Computer is a solid choice for cyclists who want to track fundamental ride metrics like speed, distance, and time, with the added benefit of cadence and acceleration data. Its user-friendly design, weather resistance, and large display make it a reliable companion for training and performance optimization. However, for those seeking advanced features like GPS navigation or extensive connectivity, exploring alternatives would be beneficial.

Specs comparison

Favorite On Favorite Off
Battery LifeUp to 40 hoursup to 5 hours
Connectivity Typewiredwired
DistanceYesYes
FunctionsAccelerometer, Cadence meter, Speedometer, Odometers12

Specs vs competitors

Favorite On Favorite Off
Favorite On Favorite Off
Favorite On Favorite Off
Favorite On Favorite Off
Favorite On Favorite Off
Battery LifeUp to 40 hourslong battery lifemore than 30 hours45 hours365 days5 days
Water ResistanceIPX6IPX8IPX6IP67waterproof-
Connectivity Typewiredwiredwirelesswirelesswireless-
DistanceYesYesYes--Yes
FunctionsAccelerometer, Cadence meter, Speedometer, OdometersCurrent Speed, Average Speed, Comparison of Current / Average Speed, Maximum Speed, Distance, Total Distance (Bike 1 / Bike 2), Ride Time, Total Ride Time (Bike 1 / Bike 2), Clock (12/24h), Current Altitude, Current Gradient, Altitude Uphill, Total Altitude Uphill (Bike 1 / Bike 2), Maximum Altitude, Current Temperature, Two Adjustable Bike Profiles, Backlight-Distance, Speed, Time, Altitude, Temperature, Calories, Slope, Lap12Clock, Trip Time, Speed (Current, Average, Max), Speed Comparison Arrow, Trip Distance, Calories Consumption, Backlight, Maintenance Reminder, Riding Data File Storage, Temperature, Cadence (Current, Average, Max), Heart Rate (Current, Average, Max), Actual Altitude, Sensor Low Battery Indicator
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