Armin Strom Skeleton watches

The Armin Strom Skeleton family covers two openworked lines that share one case: the Skeleton Pure and the Tourbillon Skeleton. Both come in four versions named after the elements, Air, Earth, Fire and Water, and the element sets the case: titanium for Air, PVD-coated steel for Earth, rose gold for Fire and plain steel for Water.

Armin Strom presented the Skeleton Pure in 2014 in two stages: Fire and Water at Salon SIAR in Mexico City in October, Air and Earth at SalonQP in London in November. Each element was made in an edition of 100, with Earth in black PVD-coated steel and Fire in 18k rose gold. Inside is calibre ARM09-S, a skeletonised, hand-wound movement with two barrels and an 8-day power reserve, showing hours, minutes, small seconds and the remaining reserve. It is the same movement as in the more classically styled One Week Skeleton; here its layers are picked out with 3D PVD colouring. On the Water, the main plate is blue PVD and shows through a sapphire dial.

The Tourbillon Skeleton keeps the 43.4 mm, 13 mm thick case and the sapphire crystal but swaps in calibre ATC11-S, with a tourbillon where the Skeleton Pure has its power reserve display.