Polar H10 Heart Rate Sensor, M-XXL
Polar H10 Heart Rate Sensor, M-XXL
Keep the watch you've got: the H10 pairs with most sports watches.
A chest strap that reads your heart electrically, right at the source, and sends it to your watch, phone app or gym bike over Bluetooth and ANT+ at once. Built for the sessions where heart rate moves fast: intervals, cycling and the gym.

Made for the sessions that move fast
On a 30-second effort, your heart rate climbs fast and drops fast. A chest strap reads it electrically, through electrodes against your skin, so the number on your watch follows the rise and the recovery as they happen. Polar calls the H10 the most accurate sensor in its history. Run your intervals by it and you'll see what each rep actually cost.

Your watch and your bike, both listening
The H10 sends your heart rate over Bluetooth and ANT+ at the same time, and two Bluetooth devices can connect at once. So your watch records the session while the indoor bike or training app shows it on the big screen. It also works with gym machines that use Polar's older 5 kHz signal.

Wet it, fasten it, clip it on
Wet the electrode areas on the back of the strap, fasten it snugly round your chest and clip the sensor on. The textile strap has non-slip silicone spots that help it stay where you put it, through sprints and out-of-the-saddle climbs.

Unclip, rinse, done
After a session, unclip the sensor and rinse the strap under the tap. When it needs a proper clean, the strap goes in the washing machine at 40 °C, in a wash bag, with no softener. The battery is a standard CR2025 coin cell you change yourself, and Polar rates it at about 400 hours.
| Polar Pro Strap size | Fits a chest of | Amazon UK |
|---|---|---|
| M-XXL (this page) | 71 to 118 cm | This listing |
| XS-S | 62 to 82 cm | A separate listing; choose it on Amazon |
Measure round your chest where the strap will sit, snug but not tight. If you measure under 71 cm, choose XS-S. Between 71 and 82 cm both sizes fit: pick XS-S if you're nearer 71 cm, so the strap isn't at the end of its adjustment. These are Polar's own figures; Amazon's listing shows different ones, so go by Polar's.

A strap that keeps up with your intervals and pairs with most sports watches.
Opens the Polar H10 M-XXL on Amazon UK.
Before your first run
Pair it with the Polar Flow app once to get any firmware update, then pair it with your watch or app as usual. Bluetooth and ANT+ don't work underwater, so in the pool it won't reach your watch, even though the sensor is water resistant to 30 m. And it's a training tool: Polar says it's designed to measure heart rate, not for medical use.
| Product | Polar H10 Heart Rate Sensor with Polar Pro Strap |
| Size | M-XXL, fits chests of 71 to 118 cm (XS-S, 62 to 82 cm, sold separately) |
| How it measures | Electrical, through electrode areas on the strap |
| Connections | Bluetooth, ANT+ and Polar GymLink (5 kHz), all on by default |
| At once | Two Bluetooth connections at the same time |
| Works with | Devices that read the Bluetooth Heart Rate Service or the ANT+ heart rate profile; a phone needs an app |
| Battery | CR2025 coin cell, user-changeable, about 400 hours |
| Water | Water resistant to 30 m; Bluetooth and ANT+ don't transmit underwater |
| Sensor size and weight | 65 x 34 x 10 mm; 21 g, or 60 g with the strap |
| Operating temperature | -10 to +50 °C |
| Strap | Textile with silicone grip spots; 38% polyamide, 29% polyurethane, 20% elastane, 13% polyester |
| Care | Rinse after every use; machine wash the strap at 40 °C; never machine wash the sensor |
| Guarantee | Polar's limited international guarantee, 2 years from purchase |
- Will the Polar H10 work with my watch?
- If your watch, app or gym machine can read a Bluetooth or ANT+ heart rate sensor, yes. The H10 sends both signals at once, and two Bluetooth devices can connect to it at the same time. Older Polar watches and gym kit that use Polar's 5 kHz signal work too.
- Is a chest strap better than my watch's wrist sensor?
- For steady runs a well-fitted wrist sensor is often close enough. For short intervals, cycling and gym work, where heart rate rises and falls quickly, a chest strap reading your heart electrically follows the changes more closely. Our guide on chest straps vs wrist heart rate shows how to test your own watch.
- Which size do I need?
- Go by Polar's chart: M-XXL fits chests of 71 to 118 cm and XS-S fits 62 to 82 cm. Measure round your chest where the strap will sit. Amazon's listing gives different figures, so use Polar's.
- How do I wash the strap?
- Unclip the sensor and rinse the strap under running water after every session. Machine wash it at 40 °C, ideally in a wash bag, with no bleach or softener, and don't tumble dry it. The sensor itself never goes in the machine.
- How long does the battery last?
- Polar rates the CR2025 coin cell at about 400 hours. You change it yourself by levering the cover open, and then pair the sensor again.
- Can I swim with it?
- It's water resistant to 30 m, but Bluetooth and ANT+ don't work in water, so your watch won't pick it up while you swim. Rinse the strap and sensor after pool or sea water.
- Is it a medical device?
- No. Polar says the H10 is designed to measure heart rate for training, with no other use intended. If you have a pacemaker or another implanted device, check with your doctor first, as Polar advises.

Clip it on, pair it once, and train by a heart rate that keeps up.
Size M-XXL fits 71 to 118 cm. XS-S is on Amazon too.
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