Dutchman Piet Hein Eek's tube watch began as a tube clock. And Piet Hein Eek's tube clock had even more humble beginnings as a tube and an extrusion ring. Piet turned to extrusion molding to design his clock face. It's a technique of forcing aluminum through a mold, and then using the extrusion profile for the material's shape. Tube watch vendor Leff Amsterdam says the process had never been applied to timepieces before, and the results were both simple and genius. Plus "a textbook example of the Dutch mentality: the idea of keeping things normal and down-to Earth."
So from the original tube clocks we now have Piet Hein Eek tube watches, smaller extruded rings setting the shape for wrist-sized clock faces and a complementary minimalist design. The Watches come in a variety of styles and colors. I like the D38 myself. Black on black with a leather strap, please. If you prefer a little more flash, go for the silver or gold watch face or steel band.
Tube watch hour and minute indicators are integrated into their cylindrical casings rather than printed on the face. The watches are water resistant to 5ATM.