The Seiko 1E20-5840 is a watch model based on the 1E20 movement.
Parts List
| REBN28JM | crystal |
| REBN28JM01 | crystal - crystal (inorganic) |
| 30M98NA1 | crown |
| 0H1400N01 | case back gasket - case back gasket |
| 0H1400N0 | case back gasket |
| DZ0041B0 | case back gasket |
| Z5220C | band - metal band |
| Z5220D-LKG | band - link |
| Z5220C-LKG | band - link |
| Z5220D | band - metal band |
| Z5220D-BK4G | clasp - clasp |
| Z5220C-PB1 | clasp - parts for buckle/clasp |
| Z5220D-PB1 | clasp - parts for buckle/clasp |
| Z5220C-BK4G | clasp - clasp |
| 03V12DGH | others - hour hand |
| 03V12DGM | others - minute hand |
| 0351931 | others - winding stem |
| 81180229 | others - bracelet fixing pipe |
| 82723120 | others - case ring |
| 81604169 | others - bracelet fixing pin |
| 1E201460X994 | others - dial |
| 1E201460XN14 | others - dial |
| 1E205840 | others - case back |
| 1E2058402E | others - case |
| 1E205840HE | others - case |
| 1E208 | others - machine code |
| DZ0041B01 | others - crown and stem gasket |
Caliber 1E20
