Technical sheet

Union 21TW cycling computer

Name: Union 21TW cycling computer
Brand: Union
SKU: 137577839
Price: 51.49 EUR
Availability: InStock
Rating: 4 (1 reviews)

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1 Reviews

3 Questions

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Size

Long

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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

Accelerometer

Product Type Odometers

Product Type

Odometers

Key differentiators

Clear and easy-to-read LCD display for at-a-glance data.

Extended battery life of up to 40 hours for long-distance rides.

Features an IPX6 water resistance rating for reliable performance in wet conditions.

Includes a cadence sensor to help optimize pedaling efficiency.

Offers a balanced, user-friendly interface for tracking key metrics.

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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Include AI Generated questions and answers

2026-07-23

Generated by AI and verified

Is the Union 21tw cycling computer difficult to set up?

Answer of Generated by AI and verified

The Union 21tw is designed for simple installation. As a wired device, it connects directly to its sensors, offering a straightforward setup process so you can start tracking your rides quickly.

* Generated by AI based on customer and product data

2026-07-23

Generated by AI and verified

Does the Union 21tw have GPS for navigation?

Answer of Generated by AI and verified

No, the Union 21tw cycling computer does not have GPS functionality. It focuses on providing core ride metrics such as speed, distance, time, and cadence through its direct sensors.

* Generated by AI based on customer and product data

2026-07-23

Generated by AI and verified

Can I use the Union 21tw in the rain?

Answer of Generated by AI and verified

Yes, the Union 21tw is designed to be durable and weather-resistant. It has an IPX6 water resistance rating, which means it is protected against powerful water jets, making it suitable for use in rainy conditions.

* Generated by AI based on customer and product data

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Frequently bought together

Best sellers

Use cases

Performance Training & Fitness Improvement 90% Fit

The inclusion of a cadence sensor provides crucial data for optimizing pedaling efficiency and technique. This makes the device a solid upgrade for cyclists focused on structured training and improving their overall performance.

Cadence Sensor Included,Long Battery Life

Long-Distance Touring & Endurance Rides 85% Fit

With a battery life of up to 40 hours, this computer can reliably track multi-day tours or extended endurance events without frequent recharging. Its IPX6 water resistance ensures it remains functional even when caught in heavy rain.

Up to 40 hours battery life,IPX6 Water Resistance

All-Weather Commuting 75% Fit

The IPX6 rating provides strong protection against powerful water jets, making it a reliable companion for daily commuters who ride in all weather conditions, including heavy rain. The long battery life also means less frequent charging for daily use.

IPX6 Water Resistance,Up to 40 hours battery life

Recreational Road & Gravel Cycling 70% Fit

This is a great all-rounder for recreational riders looking for a reliable upgrade. The clear LCD display provides essential ride stats, while the included cadence sensor offers a step up into more detailed performance tracking for those looking to improve.

Cadence Sensor Included,LCD Display

Best for

Best for Regular

The IPX6 water resistance ensures reliability in varied weather, while the long battery life supports a full week of commuting without needing a recharge.

The IPX6 rating protects against powerful water jets, suitable for heavy rain, and the 'Up to 40 hours' battery life minimizes charging frequency.

Ideal for Weekend Upgraders

The included cadence sensor provides crucial data for training efficiency, offering a significant step up from entry-level computers.

The 'cadence_sensor: Yes' attribute allows for real-time tracking of pedaling rate, a key metric for performance optimization.

Great for Data-Driven Casual Riders

This computer provides a user-friendly interface for accessing real-time ride analytics, making performance tracking simple and accessible.

Based on product features

A Solid Choice for Urban Cyclists

With its robust water resistance and long battery life, this device is built to handle the demands of daily urban cycling and enhance ride safety.

Based on product features

Benefits

FunctionalRide Longer, Charge Less

Enjoy multi-day tours and long-distance rides without the constant worry of recharging. With an impressive battery life of up to 40 hours, you can focus on your journey and performance, knowing your device will keep up.

battery_life: Up to 40 hours

FunctionalPerform Confidently in Any Weather

Don't let unpredictable weather cut your ride short. The IPX6 water resistance rating ensures your cycling computer is protected against powerful water jets, allowing you to ride through heavy rain with confidence that your device will remain functional.

water_resistance: IPX6

FunctionalOptimize Your Pedaling for Peak Performance

Take your training to the next level by monitoring your pedaling rate in real-time. The included cadence sensor provides crucial data to help you maintain an efficient and consistent pedal stroke, improving your overall cycling technique and endurance.

cadence_sensor: Yes

FunctionalView Your Stats Clearly at a Glance

Instantly read your speed, distance, and other key metrics on a clear and straightforward display. The LCD screen offers a simple, energy-efficient way to keep track of your ride data without unnecessary complexity.

display_type: LCD

Ideal buyer profiles

The Data-Driven Cyclist

This rider is focused on improving their performance and uses data to track progress and optimize training. They value detailed metrics to understand their pedaling efficiency, effort, and overall ride dynamics.

The Union 21tw is an excellent match due to its included cadence sensor, which provides crucial data for analyzing pedaling efficiency. The high score for 'Real-Time Ride Analytics' and a long battery life of up to 40 hours ensure they can capture data from even their longest training sessions without interruption.

The All-Weather

This individual relies on their bicycle for daily transportation, regardless of the weather. They need a dependable, easy-to-use device that can withstand the elements and provide essential ride information at a glance.

With its IPX6 water resistance rating, the Union 21tw is built to handle wet conditions, making it a reliable choice for year-round commuting. The impressive 40-hour battery life means less frequent charging, and the user-friendly LCD interface allows for quick checks on stats during the daily ride.

The Weekend Recreational Rider

This cyclist enjoys leisurely rides on weekends and wants to track their basic stats without being overwhelmed by complex features. They appreciate a straightforward device that is easy to set up and use from the first ride.

This product's high score for 'User-Friendly Interface' makes it ideal for casual cyclists. The clear LCD display and simple operation allow for easy tracking of key metrics, while the long battery life means it's always ready for a spontaneous weekend adventure.

Competitive features

When evaluating the Union 21tw Cycling Computer alongside other options in its category, it's important to look at the specific features each device offers. The provided data shows a very narrow field of comparison, with all listed devices having similar baseline specifications. The Union 21tw is described as a durable, weather-resistant device focused on core metrics like speed, distance, and time, with integrated sensors for acceleration and cadence.

Where it excels

The product description highlights its focus on core cycling metrics, making it a straightforward choice for riders who need essential data without complexity. | Integrated sensors for acceleration and cadence are noted, offering deeper insights into cycling dynamics for performance optimization.

Consider alternatives if...

The comparison data provided is limited, showing no differentiation across key features like altimeter, battery life, cadence sensor, color display, or connectivity for any of the listed models. Cyclists requiring advanced features such as GPS, map support, heart rate monitoring, or specific connectivity options like ANT+ or Wi-Fi would need to seek more detailed specifications to find a suitable match, as these are not confirmed for the Union 21tw or its competitors in the provided data.

Verdict

Based on the available information, the Union 21tw Cycling Computer presents itself as a solid, foundational tool for cyclists. Its description emphasizes durability and the tracking of essential performance data, including acceleration and cadence. However, the comparison matrix is uniform across all products, indicating no clear advantage or disadvantage in the listed technical specifications. It appears to be a reliable choice for those whose needs align with its described features of tracking speed, distance, time, and cadence.

Specs comparison

	Union 21TW cycling computer	Union Basic 8 Functions Cycling Computer
Battery Life	Up to 40 hours	Long-lasting
Water Resistance	IPX6	Weather-resistant

Specs vs competitors

	Union 21TW cycling computer	Cycplus M1 Cycling Computer	Bryton Rider 17e Cycling Computer	Bbb Dashboard 12 Bcp-16w Cycling Computer	Brn Cycling Computer
Battery Life	Up to 40 hours	more than 30 hours	25 hours	-	-
Water Resistance	IPX6	IPX6	Incidental Exposure To Water Of Up To 1 Meter For Up To 30 Minutes	Waterproof housing	-