[nabla9]

You don't need chest belt. I can go running without the strap and use only the HRM from wrist (it's optical).

The chest band is still more accurate (and cheaper). It gets the minor variations in HR from beat to beat. When you get closer to your maximum HR your hard beat gets more even. HR variability gives more info.

[founderling]

Now I am confused. You can use the "Polar H10" on your wrist? The product description seems to only mention strapping it to your chest.

[nabla9]

Heh, no. I have Polar M430 and H10.

M430 in my wrist. It has it's own optical HR sensor. It does not need H10 to measure HR. Polar H10 is the chest strap, it used electrodes with skin contact to measure HR.

When H10 is available and paired to M430, M430 uses H10 to get more accurate HR measurement data from the strap.

H10 works also alone with a free Polar app so you don't need the wrist monitor, although M430 has GSP and screen so it can measure also distance.