Seiko 4M21A Movement Parts Catalogue and Technical Guide
Parts catalogue and technical guide for the Seiko 4M21A automatic movement. Includes movement specifications (26.4 mm diameter, 2.7 mm height, 3 hands), step motor driving system with load compensated pulse type, automatic generating system with power reserve indicator, overcharge prevention and energy depletion forewarning functions. Contains detailed exploded view diagrams with numbered parts identification (46 numbered components total), lubrication guidance with Moebius A and SEIKO Watch Oil S-6, and disassembly/reassembly procedure references. Features 9 jewels, polyacene lithium capacitor power supply, approximately 72 hours charge duration, and 0.5-2.3V operating voltage range.
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Document Details
- Format
- Pages
- 4
- Size
- 2.4 MB
- Category
- Horlogerie