The Seiko 4N20-0018 is a watch model based on the 4N20 movement.
Parts List
| 190A02SN01 | crystal - crystal |
| 190A02SN | crystal |
| 190N91SN00 | crystal - crystal |
| 190N91SN | crystal |
| 25N07NA1 | crown - crown |
| 0D185BAA1 | case back gasket - case back gasket |
| 0D185BAA | case back gasket |
| BJA49G | band |
| ZJJ21G | band - leather band |
| BJJ61G | band |
| A130AS | others - push pin (for lb) |
| 4N200018 | others - case back |
| 4N20001825 | others - case |
| 4N200020XS19 | others - dial |
| 4N200030XS14 | others - dial |
| 4N200040XS19 | others - dial |
| 4N200090XS19 | others - dial |
| 4N200100XS14 | others - dial |
| 4N2060 | others - machine code |
| 82832635 | others - case ring |
| DZ0040B01 | others - crown and stem gasket |
| 07Y23V1H | others - hour hand |
| 07Y23VGM | others - minute hand |
| 08Y25VFM | others - minute hand |
| 07Y51VGM | others - minute hand |
| 08Y25JGM | others - minute hand |
| 07Y07VBM | others - minute hand |
| 08Y25VAH | others - hour hand |
| 07Y51V1H | others - hour hand |
| 08Y25JCH | others - hour hand |
| 07Y07VEH | others - hour hand |