The Seiko 5Y23-8A90 is a watch model based on the 5Y23 movement.
Parts List
| 290W85LN01 | crystal - crystal (inorganic) |
| 35MK9NN1 | crown |
| 35MK9NS1 | crown |
| 0F296BA11 | case back gasket - case back gasket |
| DH0100B01 | case back gasket - crown and stem gasket (4h) |
| 86584410 | crystal gasket - plastic gasket for crystal |
| 86584415 | crystal gasket - plastic gasket for crystal |
| 86584830 | bezel gasket - plastic gasket for bezel |
| T1009G | band - metal band |
| T1009S | band - metal band |
| 12P55KKH | hand - hour hand |
| 12P55KKM | hand - minute hand |
| 3AA125F3A6S | others - second hand |
| 3AA125F3ANG | others - second hand |
| 0351105 | others - winding stem |
| 0801722 | others - date dial |
| 12SC23T2 | others - second hand |
| A180BS | others - push pin |
| 5Y238A90 | others - case back |
| 5Y238A9061 | others - case |
| 5Y238A9061A | others - case |
| 5Y238A9075 | others - case |
| 5Y238D2LXB13 | others - dial |
| 5Y238D2LXG14 | others - dial |
| 5Y238D2LXS13 | others - dial |
| 82342411 | others - bezel |
| 82342419 | others - bezel |
| 82732990 | others - case ring |
| 12P55KSH | others - hour hand |
| 12SC23T1 | others - second hand |
| 12P55KSM | others - minute hand |
| 12P55KGM | others - minute hand |
| 12P55KGH | others - hour hand |