The Seiko 1F21-5B40 is a watch model based on the 1F21 movement.
Parts List
| ESCW12SN01 | crystal - crystal |
| 6K30A0SNG1 | crown |
| 0F190NA1S | case back gasket - case back gasket |
| DA69BW | band - band |
| 3BA075F1BNG | others - second hand |
| 1BB037A1BAF | others - hour hand |
| 2BB060A1BAF | others - minute hand |
| 0351807 | others - winding stem |
| 1F215B4075 | others - case |
| 82834320 | others - case ring |
| 1F215B40 | others - case back |
| 1F211B80XG14 | others - dial |
| 1F215 | others - machine code |
| A130BS | others - push pin |
| EZ0035B01 | others - crown and stem gasket |