The Seiko 4M21-0B40 is a watch model based on the 4M21 movement.
Parts List
| 280A02SN02 | crystal - crystal |
| 8M35Z0SNGA | crown - crown |
| 8M35Z0SNWA | crown - crown |
| 0F270NA1S | case back gasket - case back gasket |
| 80607941 | pusher - button |
| 80607949 | pusher - button |
| 4G24KB | band - band |
| 4G24BB | band - band |
| 44H7LB | band - band |
| 44H7AB | band - band |
| 44H7JB | band - band |
| 44H7ZB | band - metal band |
| 44H7HB | band - metal band |
| 44H7XB | band - metal band |
| 4G23LB | band - leather band |
| 44H7CB | band - band |
| 44H7FB | band - metal band |
| 4G24KB-LB | band - leather without buckle |
| 4G24YB | band - leather band |
| 4G24YB-LB | band - leather without buckle |
| 4G24BB-LB | band - leather without buckle |
| 4G24GB | band - leather band |
| 44H7AB-LK3 | band - link |
| 44H7CB-LKG | band - link |
| 4G23CB | band - leather band |
| 4G23CB-LB | band - leather without buckle |
| 44H7FB-LK5 | band - link |
| 44H7LB-LKG | band - link |
| 44H7XB-LK2 | band - link |
| 44H7ZB-LK6 | band - link |
| 44H7HB-LK3 | band - link |
| 44H7JB-LKS | band - link |
| 44H7FB-BKI | clasp - buckle |
| 44H7FB-PB1 | clasp - parts for buckle |
| 44H7CB-BKI | clasp - buckle |
| 44H7CB-PB1 | clasp - parts for buckle |
| 44H7XB-BK | clasp - buckle |
| 44H7XB-PB1 | clasp - parts for buckle |
| 44H7AB-BKI | clasp - buckle |
| 44H7AB-PB1 | clasp - parts for buckle |
| 44H7LB-BK7G | clasp - buckle |
| 44H7LB-PB1 | clasp - parts for buckle |
| 44H7HB-BKI | clasp - buckle |
| 44H7HB-PB1 | clasp - parts for buckle |
| 44H7ZB-BKL | clasp - buckle |
| 44H7ZB-PB1 | clasp - parts for buckle |
| 44H7JB-BK7S | clasp - buckle |
| 44H7JB-PB1 | clasp - parts for buckle |
| 3AA125F0ANG | others - second hand |
| 3AX115F5ANG | others - second hand |
| 3AX115F5AAL | others - second hand |
| 3AA125F0ANS | others - second hand |
| 2BA120L0BDG | others - minute hand |
| 2BC110A0BAL | others - minute hand |
| 2BA120L0BDS | others - minute hand |
| 1BA085L0BDG | others - hour hand |
| 1BC070A0BAL | others - hour hand |
| 1BA085L0BDS | others - hour hand |
| 0351552 | others - winding stem |
| 81400709 | others - button spring clip |
| EG0060B01 | others - button gasket |
| 81606439 | others - bracelet fixing pin |
| 81190055 | others - bracelet fixing pipe |
| 82837180 | others - case ring |
| 4M210B4061 | others - case |
| 4M210B40 | others - case back |
| 4M210B4061A | others - case |
| 4M210B406Y | others - case |
| 4M210B406YA | others - case |
| 4M210B40RHA | others - case |
| 4G23CB-EP8 | others - endpiece |
| 4G24BB-EP9 | others - endpiece |
| 4G24KB-EP9 | others - endpiece |
| 4G24YB-EP9 | others - endpiece |
| 4M210B70XG14 | others - dial |
| 4M210B70XS13 | others - dial |
| 4M210B70XS24 | others - dial |
| 4M210C90XS19 | others - dial |
| 4M211 | others - machine code |
| 44H7HB-EP1 | others - endpiece |
| 4M210B40RH | others - case |
| 44H7FB-EP2 | others - endpiece |
| 44H7LB-EPG | others - endpiece |
| 44H7JB-EPS | others - endpiece |
| AD006BA12 | others - crown gasket |
Caliber 4M21
Other models with the same movement
| 4M21-0010 |
| 4M21-0A10 |
| 4M21-0A20 |
| 4M21-0A30 |
| 4M21-0A40 |
| 4M21-0A50 |
| 4M21-0A60 |
| 4M21-0A70 |
| 4M21-0A80 |
| 4M21-0A90 |
| 4M21-0B00 |
| 4M21-0B0A |
| 4M21-0B10 |
| 4M21-0B20 |
| 4M21-0B30 |
| 4M21-0B50 |
| 4M21-0B60 |
| 4M21-0B70 |
| 4M21-0B80 |
| 4M21-0B90 |
| 4M21-0C00 |
| 4M21-0C10 |