The Seiko 1221-5720 is a watch model based on the 1221 movement.
Parts List
| ESXN27SN00 | crystal - crystal (sapphire) |
| 30NE1DA5 | crown - crown |
| 0F150NA11 | case back gasket - case back gasket |
| HK68A | band - leather band |
| 06SS01VG | hand - second hand |
| 07S45JGH | hand - hour hand |
| 07S45JGM | hand - minute hand |
| 07S45VGH | hand - hour hand |
| 07S45VGM | hand - minute hand |
| A130AS | others - push pin (for lb) |
| DZ0040B01 | others - crown and stem gasket |
| 0351117 | others - winding stem |
| 122110 | others - machine code |
| 12211020XG14 | others - dial |
| 12211190XG18 | others - dial |
| 12215720 | others - case back |
| 1221572025A | others - case |
| 1221572025B | others - case |
| 1221572025C | others - case |
| 1221572025D | others - case |
| 1221572025X | others - case |
| 82721630 | others - case ring |
Caliber 1221
