The Seiko 2P21-5A50 is a watch model based on the 2P21 movement.
Parts List
| SA8W40JM01 | crystal |
| 30MA2NA1 | crown - crown |
| 0A1600N01 | case back gasket |
| 86574240 | crystal gasket - plastic gasket for crystal |
| G5059G | band - metal band |
| G5059G-BK5G | clasp - clasp |
| 05T16ZBH | hand - hour hand |
| 05T20ZGH | hand - hour hand |
| 05T20ZGM | hand - minute hand |
| 05T26ZBM | hand - minute hand |
| 07SC02NG | others - second hand |
| EZ0035B0A | others - crown and stem gasket |
| 0351236 | others - winding stem |
| 81606439 | others - bracelet fixing pin |
| 81180229 | others - bracelet fixing pipe |
| 2P210B20XA15 | others - dial |
| 2P210B30XG14 | others - dial |
| 2P215A5075 | others - case |
| 2P219 | others - machine code |
| 82733920 | others - case ring |
| EZ0035B01 | others - crown and stem gasket |
Caliber 2P21
