The Seiko 7N42-8120 is a watch model based on the 7N42 movement.
Parts List
| 290P03H303 | crystal - crystal |
| 8M40A0NNG1 | crown - crown |
| FE308BAA1 | case back gasket - case back gasket |
| 86580835 | crystal gasket - plastic gasket for crystal |
| 86561970 | bezel gasket - plastic gasket for bezel |
| DAP7BW | band - band |
| DAQ7BW | band - band |
| DAP7BW-BJ00 | clasp - buckle |
| 1AB075A1BAA | others - hour hand |
| 2AB115A1BAA | others - minute hand |
| 3AA125F1ANG | others - second hand |
| 0351892 | others - winding stem |
| 7N423 | others - machine code |
| 7N428210XG14 | others - dial |
| 7N428220XS19 | others - dial |
| 89920255 | others - back plate |
| A180BS | others - push pin |
| 82851310 | others - case ring |
| 7N42812075A | others - case |
| 82292035 | others - bezel |
| 7N428120 | others - case back |
| 2AB115A1BAF | others - minute hand |
| 1AB075A1BAF | others - hour hand |
| AD006BA12 | others - crown gasket |