The Seiko 1F21-0BL0 is a watch model based on the 1F21 movement.
Parts List
| RE8A36SB0B | crystal - crystal (sapphire) |
| RE8A36SB0C | crystal - crystal (sapphire) |
| 6K40C6STGA | crown - crown (3h) |
| 6K40C6STGB | crown - crown (3h) |
| 0F200BAD2 | case back gasket - case back gasket |
| DA381KM | band - metal band |
| DA381KMLK | band - link |
| DA382RM | band - metal band |
| DA382RMLK | band - link |
| N0HN22SA00B | clasp - clasp |
| N0HN22SE00B | clasp - clasp |
| 2BG070L0BD2 | hand - minute hand |
| 2BG070L0BDM | hand - minute hand |
| 1BG045L0BD2 | hand - hour hand |
| 1BG045L0BDM | hand - hour hand |
| 3BA075F0BNG | others - second hand |
| 3BA075F0BNZ | others - second hand |
| 0351807 | others - winding stem |
| AC004BAD1 | others - crown and stem gasket |
| 81606439 | others - bracelet fixing pin |
| 81181459 | others - bracelet fixing pipe |
| 81190055 | others - bracelet fixing pipe |
| 81607579 | others - bracelet fixing pin |
| 1F210BL0 | others - case back |
| 1F210BL001A | others - case |
| 1F210BL002A | others - case |
| 1F210CM0XS15 | others - dial |
| 1F210CM0XY15 | others - dial |
| 1F213 | others - machine code |
| 82846520 | others - case ring |