Forerunner 910XT was designed with size in designers mind.Initial size is: WxHxD: 5.4 x 6.1 x 1.5 cm

When comparing it to FR310XT with measures: WxHxD: 5.4 x 5.6 x 1.9 cm, we can see its difference in height and that the new 910XT is a lot slimmer.
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And not only smaller than FR310XT and FR305 but the new FR910XT is the smallest GPS sports watch Garmin has ever created.

The strap it uses is durable and water-proof.