The Seiko 1F21-1A40 is a watch model based on the 1F21 movement.
Parts List
| 200W36SK01 | crystal |
| 25MA2NA4 | crown |
| 0A1800N01 | case back gasket |
| 81180601 | band - bracelet fixing pipe |
| Z1551 | band - metal band |
| 81180229 | others - bracelet fixing pipe |
| 81604259 | others - bracelet fixing pin |
| 82821060 | others - case ring |
| 1F211A40 | others - case back |
| 1F211A409T | others - case |
| 1F211B40XS14 | others - dial |
| 1F219 | others - machine code |
| 86502905 | others - decorative plate |
| 0351807 | others - winding stem |
| 08SC653G | others - second hand |
| 08TH8DGH | others - hour hand |
| 08TH8DGM | others - minute hand |