The Seiko 8Y21-0020 is a watch model based on the 8Y21 movement.
Parts List
| 160A02JN02 | crystal - crystal (inorganic) |
| 160N83JN00 | crystal |
| 35M75NN1 | crown |
| 0G1820B09 | case back gasket - case back gasket |
| 0G1820B01 | case back gasket |
| DH0115B01 | case back gasket - crown and stem gasket |
| B5525G NL | band |
| M5089G NL | band |
| M5089G | band |
| B5574G | band |
| B5574G NL | band |
| B5574G-BK3G | clasp - clasp |
| M5089G-BK3G | clasp - clasp |
| 07P31NGH | hand - hour hand |
| 07P31NGM | hand - minute hand |
| 07P27DGH | others - hour hand |
| 07P27DGM | others - minute hand |
| 2AA065A1BDG | others - minute hand |
| 2AA065A1BNG | others - minute hand |
| 2AG060LABNG | others - minute hand |
| 1AG040LABNG | others - hour hand |
| 07SC25NG | others - second hand |
| 3BA075F1BNG | others - second hand |
| 1AA042A1BNG | others - hour hand |
| 1AE040LMBNG | others - hour hand |
| 2AE060LABNG | others - minute hand |
| 06SC11NG | others - second hand |
| 0351112 | others - winding stem |
| 82739350 | others - case ring |
| 8Y210020 | others - case back |
| 8Y21002025A | others - case |
| 8Y210080XS14 | others - dial |
| 8Y210090XB14 | others - dial |
| 8Y210090XS14 | others - dial |
| 8Y210270XB14 | others - dial |
| 8Y210270XG14 | others - dial |
| 8Y210270XR14 | others - dial |
| 8Y210350XB14 | others - dial |
| 8Y210350XG24 | others - dial |
| 8Y210350XR14 | others - dial |
| 8Y210360XB14 | others - dial |
| 8Y210360XG14 | others - dial |
| 8Y210360XR14 | others - dial |
| 8Y2183 | others - machine code |
| B090BS | others - push pin |
| 05SC05NG | others - second hand |
| 1AF040LABNG | others - hour hand |
| 2AF060LABNG | others - minute hand |
| 1AE045LABNG | others - hour hand |
| 2AE065LABNG | others - minute hand |
| 07P49CGM | others - minute hand |
| 07P31DGM | others - minute hand |
| 06P47NGM | others - minute hand |
| 05P13NGM | others - minute hand |
| 06P07DGM | others - minute hand |
| 06P57NGM | others - minute hand |
| 06P47NGH | others - hour hand |
| 05P13NGH | others - hour hand |
| 06P07DGH | others - hour hand |
| 06P57NGH | others - hour hand |
| 07P49CGH | others - hour hand |
| 07P31DGH | others - hour hand |
Caliber 8Y21
