Seiko 4005 Movement Details

Seiko caliber 4005 is an automatic watch movement. Production started around 1968 and production finished in 1969.
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Sub-brands: Bell-matic
Day / date?Date only
GMT / world time?No
Chronograph?No
Alarm?Yes
Hacking?No
Rate:19,800 bph
Number of jewels:27
Lift angle:52º
Notes:The same as cal. 4006 but with date display only (no day). It has a 10-second mechanical alarm feature powered by a second mainspring. The lift angle is often listed as 58.4º but research by Martin at "Adventures in Amateur Watch Fettling" shows that the lift angle is 52º.
Related movements: 4006

Part Codes

Stem code: 354805
Balance wheel code: 310470
Mainspring code: 401805

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