The Seiko 7820-5420 is a watch model based on the 7820 movement.
Parts List
| SA2N36GN00 | crystal |
| 35R08NA1 | crown |
| 35R08NS1 | crown - crown |
| 35R30NS1 | crown |
| 35R30NA1 | crown |
| 0A2800N01 | case back gasket - case back gasket |
| LV942 | band - leather band |
| LV951 | band - leather band |
| 11C22DGM | hand - minute hand |
| 11C24DSH | hand - hour hand |
| 11C24DGH | others - hour hand |
| 11C22DSM | others - minute hand |
| 0354780 | others - setting/winding stem |
| 0884527 | others - holding ring for dial |
| 7820542011 | others - case |
| 7820542025 | others - case |
| 782055703133 | others - dial |
| 782055703134 | others - dial |
| 7820557032X4 | others - dial |
| 83107230 | others - case ring |
| A200CS | others - push pin |