The Seiko Y121-0AA0 is a watch model based on the Y121 movement.
Parts List
| 270T50ANS0 | crystal - crystal |
| 45MP8NS1 | crown - crown |
| 0F240BA1S | case back gasket - case back gasket |
| FFN9JB | band - band |
| Y1210AA002C | others - case |
| S160BS | others - push pin |
| 0354786 | others - winding stem |
| AD006BA12 | others - crown gasket |