If you have normal size wrists/arms, do not buy. This strap is not long enough, its as simple as that. I am a normal size bloke with normal wrists. Whilst the strap does go around my wrist, it only just reaches the Velcro, and is tight. It needs to be 50mm longer to be comfortable and be able to fit anyone.
When I ordered this I didn't realise it was coming from China, the delivery was a bit slow, possibly my fault for not checking. I assume it has been made for the Eastern market place. Maybe everyone has smaller wrists. This should be advertised as a Ladies wrist band.