The Seiko 1E20-3B20 is a watch model based on the 1E20 movement.
Parts List
| K01A02JR02 | crystal - crystal |
| K01A02JR | crystal |
| 30MF8NG1 | crown - crown |
| 0E150NA1S | case back gasket - case back gasket |
| EZ0035B0 | case back gasket |
| 43X5LZ | band - band |
| 43X5KZ | band - band |
| 43X5KZ-LKG | band - link |
| 43X5LZ-LKG | band - link |
| 43X5KZ-BKCG | clasp - buckle |
| 43X5KZ-PB2 | clasp - parts for buckle |
| 43X5LZ-BKCG | clasp - buckle |
| 43X5LZ-PB2 | clasp - parts for buckle |
| 03V30DGM | others - minute hand |
| 03V30DGH | others - hour hand |
| 81606439 | others - bracelet fixing pin |
| 81190055 | others - bracelet fixing pipe |
| 1E203B2025Z | others - case |
| 82837280 | others - case ring |
| 1E203B20 | others - case back |
| 1E205A88XA14 | others - dial |
| 1E205A98XG14 | others - dial |
| 1E205A98XZ14 | others - dial |
| 1E207 | others - machine code |
| 0351931 | others - winding stem |
| 1E203B202HZ | others - case |
| EZ0035B01 | others - crown and stem gasket |
Caliber 1E20
