The Seiko 3Y09-0121 is a watch model based on the 3Y09 movement.
Parts List
| 200WC3HN01 | crystal |
| 200WC3HN | crystal |
| 30MG7NS1 | crown |
| 30MG7NN1 | crown |
| FH2080B01 | case back gasket - case back gasket |
| DZ0040B0 | case back gasket |
| 86571830 | crystal gasket |
| 86170610 | bezel gasket - plastic gasket for bezel |
| G5148J-LKS | band - link |
| G5148K-LKG | band - link |
| G5148L-LKG | band - link |
| G5148J | band |
| G5148K | band |
| G5148L | band |
| G5148L-BK7G | clasp - clasp |
| G5148K-BK7G | clasp - clasp |
| G5148J-BK7S | clasp - clasp |
| T070BS | others - push pin |
| DZ0040B01 | others - crown and stem gasket |
| 0351546 | others - winding stem |
| 0801778 | others - date dial |
| 0801812 | others - date dial |
| 3Y090121 | others - case back |
| 3Y09012161 | others - case |
| 3Y09012161A | others - case |
| 3Y09012175 | others - case |
| 3Y09012198 | others - case |
| 3Y090211XG14 | others - dial |
| 3Y090211XS13 | others - dial |
| 3Y090211XS14 | others - dial |
| 3Y090211XS24 | others - dial |
| 3Y099 | others - machine code |
| 82343911 | others - bezel |
| 82343919 | others - bezel |
| 82841810 | others - case ring |
| 09T21DSM | others - minute hand |
| 09T21DGM | others - minute hand |
| 09T79DSH | others - hour hand |
| 09T79DGH | others - hour hand |