The Seiko 4N20-520A is a watch model based on the 4N20 movement.
Parts List
| RE0A43S20B | crystal |
| 30M15DA5 | crown |
| 0H2200B01 | case back gasket - rotating bezel gasket |
| AC004BA11 | case back gasket - crown and stem gasket |
| HZ03B | band - metal band |
| HK47C | band - leather band |
| 07Y736GH | others - hour hand |
| 0351156 | others - winding stem |
| 81181459 | others - bracelet fixing pipe |
| 81606759 | others - bracelet fixing pin |
| 4N200760XB14 | others - dial |
| 4N20520A | others - case back |
| 4N20520A26A | others - case |
| 4N2061 | others - machine code |
| 82843990 | others - case ring |
| 07Y736GM | others - minute hand |