The Seiko 2P21-5110 is a watch model based on the 2P21 movement.
Parts List
| SA4W77HM01 | crystal |
| SA4W77HM02 | crystal |
| 32M51NA1 | crown |
| 0F175BAA5 | case back gasket - case back gasket |
| 0Z0034B01 | case back gasket - crown and stem gasket |
| 86581810 | crystal gasket - plastic gasket for crystal |
| B5398C | band - metal band |
| B5398G | band - metal band |
| B5398G-BK5G | clasp - clasp |
| B5398C-BK5S | clasp - clasp |
| 05T21DGM | hand - minute hand |
| 05T23DGH | hand - hour hand |
| 3BA075F1BNG | others - second hand |
| 06SC15NG | others - second hand |
| A120AS | others - push pin |
| 2P210270XB16 | others - dial |
| 2P210270XG16 | others - dial |
| 2P215110 | others - case back |
| 2P21511075 | others - case |
| 2P2151107H | others - case |
| 2P219 | others - machine code |
| 82803410 | others - case ring |
Caliber 2P21
