The Seiko 2N20-0040 is a watch model based on the 2N20 movement.
Parts List
| 175N21SK | crystal |
| 175N21SK01 | crystal |
| 25N11DE1 | crown |
| 0G1600B01 | case back gasket - case back gasket |
| 0D165BA1 | case back gasket |
| 0D165BA11 | case back gasket |
| BFJ15G | band - leather band |
| BFJ27G | band - leather band |
| DZ0040B01 | others - crown and stem gasket |
| 07M27JGH | others - hour hand |
| 0351106 | others - setting/winding stem |
| 2N20004043C | others - case |
| 2N200060XG14 | others - dial |
| 2N2011 | others - machine code |
| 82801690 | others - case ring |
| A100AS | others - push pin |
| 07M27JGM | others - minute hand |
Caliber 2N20
Other models with the same movement
| 2N20-0010 |
| 2N20-0020 |
| 2N20-0050 |
| 2N20-0060 |
| 2N20-0070 |
| 2N20-0080 |
| 2N20-0090 |
| 2N20-0100 |
| 2N20-0110 |
| 2N20-0130 |
| 2N20-0140 |
| 2N20-5000 |
| 2N20-5010 |
| 2N20-5020 |
| 2N20-5030 |
| 2N20-5050 |
| 2N20-5060 |
| 2N20-5070 |
| 2N20-5080 |
| 2N20-5090 |
| 2N20-509A |