U-Boat has several collections and one of the most original and renowned of the brand is the Capsoil Collection: retro-style pieces that feature the latest innovations.
Without doubt, Capsoil pieces are known for the low viscosity oil in which their swiss electromechanical movement is immersed, and which flows into the dial. This special oil not only gives the dial a deep, three-dimensional appearance, creating the illusion that there is no glass; but it also creates a constantly moving bubble that compensates for temperature variations, amplifies the vision of the hands and makes their indexes easier to read.

Among the innovations that ensure the reliability of U-boat Capsoil are the patented system that joins the case to the glass, and the system of patented levers that withstand high pressures.
One of their newest models is the U-Boat Darkmoon, inspired by the dark side of the satellite. They stand out for their functionality as well as for their original beauty.
Available with straps made of leather, silicone or Milanese mesh, all of them share a series of common characteristics: quartz movement, curved mineral crystal, 5 atm resistance (50 m) and a dial completely filled with a special oil that makes its black color deep and intense. Inside the dial of these models an air bubble in constant movement is formed in order to compensate the temperature variations that the watch may suffer.
Most U-boat Capsoil feature a 44 mm case, except for two whose diameter is 38 mm. Regarding the materials, all of them are made of 316L stainless steel, and some of them have a subsequent IPB coating.
Another of the latest Capsoil pieces is U-Boat Rainbow: watches that are characterized by a vaulted iridescent mineral glass that creates a rainbow effect and emphasizes the infinite nuancesof the colorful dial. U-boat Capsoil Rainbow are pieces designed for fashion lovers who enjoy creativity and free style. Like the Darkmoon, the dial is completely immersed in a special oil that creates an air bubble.
Rainbow U-Boats feature leather or Milanese mesh straps and 44 mm and 38 mm cases in different and cheerful Mother-of-Pearl colors: orange, blue and pink.