Casio has announced a limited edition version of its WSD-F20 smartwatch.

The Casio WSD-F20-WE is part of its Pro Trek Smart series of watches for outdoor enthusiasts and comes in a limited colour scheme of fluorite white.

The colour is maintained with a clear-coat for protection and a deep multilayer design effect that makes it look "crystalline".

The watch itself is identical to the conventional WSD-F20 inside, running on Android Wear 2.0 and with a 1.32-inch dual layer touchscreen display (320 x 300).

It comes with GPS built-in and connects to your smartphone using Bluetooth 4.1. Battery life is claimed to last roughly a day with normal use and without GPS activated, up to 18 hours with it on and heavy use.

Along with the watch, which will be available in a run of just 1,500 units, a new "Journey" watch face is being released for the F20-WE plus already existing models.

It adds a Google Maps screen behind the watch hands and if you tap it the full map will appear on screen.

Pricing in the UK is yet to be revealed, but the standard model cost £450 when it was released at the start of last year.