The Seiko 1F21-5040 is a watch model based on the 1F21 movement.
Parts List
| ES4A23SN02 | crystal - crystal |
| 6M30B5NNG2 | crown - crown |
| 0F150BA1S | case back gasket - case back gasket |
| D0R7CQ | band - band |
| D0R7FQ | band - band |
| 1BC030A1BNG | others - hour hand |
| 2BC045A1BNG | others - minute hand |
| 3BA050F1BNG | others - second hand |
| 81606359 | others - bracelet fixing pin |
| 1F210140XS14 | others - dial |
| 1F210140XZ14 | others - dial |
| 1F215 | others - machine code |
| 0351807 | others - winding stem |
| DZ0040B01 | others - crown and stem gasket |
| 81190055 | others - bracelet fixing pipe |
| 1F21504075A | others - case |
| 82835330 | others - case ring |
| 1F215040 | others - case back |
| 1F2150407NA | others - case |