The Seiko 1F21-0BJ0 is a watch model based on the 1F21 movement.
Parts List
| RE8A34SN02 | crystal - crystal (sapphire) |
| 6K35B2SNW1 | crown - crown |
| 0F170BAD2 | case back gasket - case back gasket |
| DA311JM | band - metal band |
| DA311JMLK | band - link |
| DA312JM | band - metal band |
| DA312JMLK | band - link |
| H18H12SA00B | clasp - clasp |
| H18H12SA01B | clasp - clasp |
| 2BE050L2BD1 | hand - minute hand |
| 2BE050L2BDZ | hand - minute hand |
| 3BA050F1BNJ | hand - second hand |
| 1BE032L2BD1 | hand - hour hand |
| 1BE032L2BDZ | hand - hour hand |
| 3BA050F1BNS | others - second hand |
| A100BS | others - push pin (for mb) |
| 81190875 | others - bracelet fixing pipe |
| 81601489 | others - bracelet fixing pin |
| W090200AS | others - wave pin (band) |
| 0351807 | others - winding stem |
| AC004BAD1 | others - crown and stem gasket |
| 1F210BJ0 | others - case back |
| 1F210BJ001A | others - case |
| 1F210CK0XS1Z | others - dial |
| 1F210CL0XB13 | others - dial |
| 1F215 | others - machine code |
| 82846460 | others - case ring |