The Seiko/TMI/SII caliber NH37 is a hand-windable, hacking variation of the widely popular caliber NH35A – one of the world’s most popular automatic movements and is widely available in many affordable/microbrand watches. In comparison, the NH37A listed here has an additional complication: a 24 hour indicator. This is the only difference between the NH35 and NH37.
Crown Position Functions:
0 (against the case): Clockwise = Manual Winding / Counterclockwise = Nothing
1 (pulled out one click): Clockwise = nothing / Counterclockwise = Date setting
2 (pulled out two clicks): Time setting clockwise and counterclockwise
Interesting Note: Time Module aka Seiko Instruments labels the NH calibers as part of the “Basic” Mechanical Series. They also have NE calibers that are labeled as “Premium” Mechanical Series.