Series 31

Series 31

The pocket watch movement that has been redesigned to feature an indirect central second hand makes this watch an elegant choice. A key feature of the movement remains the secret of the wearer – the second stop.

To precisely set the time of a wrist watch most movements are equipped with a second stop – when the crown is wound, the second hand doesn’t move. The seconds zeroing is a much rarer design.

When the crown is wound, the second hand continues to run until it reaches “60” and then it automatically stops – thus it is possible to use a time signal to set the watch to the second.

Model Overview Series 31

31.HS-12.1

Modell 31.HS-12.1

Bezel
fixed bezel

Case
stainless steel polished, case sides in satin finish

Dial and Hands
deep black dial, hands made in steel

Special features
Nivarox hairspring, swan neck micrometer

31.HS-12.2

Modell 31.HS-12.2

Bezel
fixed bezel

Case
stainless steel polished, case sides in satin finish

Dial and Hands
deep black dial, hands made in steel

Special features
Nivarox hairspring

31.HS-14.2

Modell 31.HS-14.2

Bezel
fixed sandblasted bezel

Case
stainless steel bead-blasted

Dial and Hands
deep black dial, hands made in steel

Special features
Nivarox hairspring

Technical details

Movement

  • Calibre HS 81
  • Base: UNITAS 6497 Lépine. Modified as per a construction by Helmut Sinn
  • indirect center second
  • second stop at 60 when crown is pulled
  • 18 jewels
  • 18000 vibrations per hour; 2.5 Hz.
  • Movement diameter 16 1/2''' (36,6 mm)
  • Incabloc shock protection
  • Glucydur balance
  • Nivarox hairspring
  • Movement decorated with Geneva Stripes , blued screw hads, crown wheel and ratchet wheel with solar finish
  • Power reserve approx. 40 hours

Functions

  • Hours, minutes, indirect center second
  • Second stop at 60 when crown is pulled

Case

  • Case made of stainless steel, polished
  • sapphire crystal glass, anti-reflective on the interior
  • screwed back with crystal glass
  • Pressure resistant up to 10 bar

Dimensions and Weight

  • Case diameter: 41.9 mm
  • Case thickness: 13.7 mm
  • Band lug width: 22 mm
  • Weight without strap: 71 Gramm