The Seiko 7N42-7B20 is a watch model based on the 7N42 movement.
Parts List
| 280W22HN01 | crystal - crystal |
| 45MP0NS1 | crown - crown |
| 45MP0NA1 | crown |
| FH2980B01 | case back gasket - case back gasket |
| 86177921 | crystal gasket - plastic gasket for crystal |
| 86179411 | bezel gasket - plastic gasket for bezel |
| 44C2CG-LK3 | band - link |
| 44C2KG-LKG | band - link |
| 44C2LG-LKG | band - link |
| 44C2JG | band - band |
| 44C2KG | band - band |
| 44C2CG | band - band |
| 44C2LG | band - band |
| 44C2AG | band - band |
| 44C2LG-BK1S | clasp - buckle |
| 44C2LG-PB1 | clasp - parts for buckle |
| 44C2KG-BK1G | clasp - buckle |
| 44C2KG-PB1 | clasp - parts for buckle |
| 44C2CG-BKA | clasp - buckle |
| 44C2CG-PB1 | clasp - parts for buckle |
| 3AX110F3ASG | others - second hand |
| 3AX110F3ASS | others - second hand |
| 1AB080A8BSG | others - hour hand |
| 2AB110A6BSG | others - minute hand |
| 1AB080A8BSS | others - hour hand |
| 2AB110A6BSS | others - minute hand |
| 82830140 | others - case ring |
| 7N427B2061 | others - case |
| 82291969 | others - bezel |
| 7N427B20 | others - case back |
| 7N427B2061Z | others - case |
| 7N427B206YZ | others - case |
| 7N427B206Y | others - case |
| 82291964 | others - bezel |
| 0351892 | others - winding stem |
| 0878580 | others - date dial |
| 0878587 | others - date dial |
| 0878588 | others - date dial |
| 0878589 | others - date dial |
| 7N427B2075Z | others - case |
| 82291961 | others - bezel |
| 7N423 | others - machine code |
| 7N427C18XG14 | others - dial |
| 7N427C18XL14 | others - dial |
| 7N427C18XN13 | others - dial |
| 7N427C18XS13 | others - dial |
| 7N427C18XS24 | others - dial |
| 7N427C20XS13 | others - dial |
| 7N427C20XS24 | others - dial |
| 7N427C28XB13 | others - dial |
| 7N427C28XL13 | others - dial |
| 7N427C28XN14 | others - dial |
| 7N427C28XS13 | others - dial |
| 7N427C28XS24 | others - dial |
| A190BS | others - push pin |
| 0Z0060B01 | others - crown and stem gasket |