The Seiko 4N21-0320 is a watch model based on the 4N21 movement.
Parts List
| 160A11SN02 | crystal |
| 25M25NA4 | crown |
| 0F140BAA3 | case back gasket - case back gasket |
| DB16B | band - metal band |
| 1BA042A1BNG | others - hour hand |
| 2BA065A1BNG | others - minute hand |
| 3DA065AABDG | others - second hand |
| 0351155 | others - winding stem |
| DZ0040B01 | others - crown and stem gasket |
| 81606439 | others - bracelet fixing pin |
| 81181459 | others - bracelet fixing pipe |
| 81606459 | others - bracelet fixing pin |
| 82833415 | others - case ring |
| 4N210320 | others - case back |
| 4N210320SAA | others - case |
| 4N210710XS14 | others - dial |
| 4N2164 | others - machine code |
| 82361615 | others - bezel |