The Seiko 2P21-5C20 is a watch model based on the 2P21 movement.
Parts List
| SA9W36JN01 | crystal |
| SA9W36JN | crystal |
| 30MA2NA1 | crown - crown |
| 0A1800N01 | case back gasket |
| EZ0035B0 | case back gasket |
| 86580540 | crystal gasket - plastic gasket for crystal |
| B5427C | band - metal band |
| B5427C-LKG | band - link |
| B5427D | band - metal band |
| B5427D-LKG | band - link |
| B5427G | band - metal band |
| B5427G-LKG | band - link |
| B5427G-BK4G | clasp - clasp |
| B5427D-BK4G | clasp - clasp |
| B5427C-BK4G | clasp - clasp |
| 07SC02NG | others - second hand |
| 0351236 | others - winding stem |
| 81180229 | others - bracelet fixing pipe |
| 81604259 | others - bracelet fixing pin |
| 2P210E40XB14 | others - dial |
| 2P210E40XG14 | others - dial |
| 2P210E40XS14 | others - dial |
| 2P215C20 | others - case back |
| 2P215C2075 | others - case |
| 2P215C2098 | others - case |
| 2P215C20XF | others - case |
| 2P219 | others - machine code |
| 82801040 | others - case ring |
| 06T22NGH | others - hour hand |
| EZ0035B01 | others - crown and stem gasket |
| 06T22NGM | others - minute hand |
Caliber 2P21
