SEIKO 6139B-903463, Automatic framework with ball bearing

• SEIKO original part in very good used condition. Picture shows the actual part.

• Part no: 903463

• Fits cal: 6139B

Technical data: SEIKO 6139B

• 17 jewels, automatic wind, chronograph, 60 s, 30 min counter, day-date.
• S: = 27.0 mm.
• H: = 8.0 mm.
• N: = 21.600 A/h.
• Power reserve: 45 h.

Versions:

• 6138A: 21 jewels.
• 6138B: 21 jewels, modified switch mechanism.
• 6139A: 21 jewels, without 12 h counter.
• 6139B: 17 jewels, without 12 h counter, modified switch mechanism.