[cameldrv]

You see the striped ones in Europe and the solid orange ones in the U.S.

It's not a precision instrument. Windsocks wear out fairly quickly. It' gives you the direction fairly accurately, and the speed say +- 5 knots, which is adequate to choose a runway and have a good initial guess of how to correct for a crosswind. Once you've started your takeoff/approach, you make corrections based on the observed behavior of the plane, e.g. on final approach, if you drift a little to the right of centerline, you correct a little to the left.