The Seiko 5Y23-5A40 is a watch model based on the 5Y23 movement.
Parts List
| ESEW31LN01 | crystal |
| ESEW31LN | crystal |
| 45EC5NN1 | crown |
| 45EC5NS1 | crown |
| FE278BAA1 | case back gasket |
| ED014BA11 | case back gasket - gasket |
| FD015BA11 | case back gasket - crown and stem gasket |
| ED014BA1 | case back gasket |
| 86591470 | crystal gasket |
| G1387K-LKG | band - link |
| T1005G | band - metal band |
| T1005S | band - metal band |
| G1387J | band |
| G1387K | band |
| G1387K-PB1 | clasp - parts for buckle/clasp |
| G1387K-BK1G | clasp - clasp |
| 10SC27T1 | others - second hand |
| 10SC27T2 | others - second hand |
| 3AA125F3A6S | others - second hand |
| 3AA125F3ANG | others - second hand |
| 0351670 | others - winding stem |
| 0801722 | others - date dial |
| 5Y235A40 | others - case back |
| 5Y235A4061 | others - case |
| 5Y235A4061A | others - case |
| 5Y235A4061B | others - case |
| 5Y235A4075 | others - case |
| 5Y235A5LXG14 | others - dial |
| 5Y235A5LXL13 | others - dial |
| 5Y235A5LXS13 | others - dial |
| 5Y235A6LXB1Z | others - dial |
| 82821930 | others - case ring |
| 84309435 | others - dial ring |
| 84309436 | others - dial ring |
| 84309437 | others - dial ring |
| 84309438 | others - dial ring |
| A180BS | others - push pin |
| 09P85MSM | others - minute hand |
| 09P85MKM | others - minute hand |
| 10P83LSM | others - minute hand |
| 09P85MGM | others - minute hand |
| 09P85MSH | others - hour hand |
| 09P85MKH | others - hour hand |
| 10P83LSH | others - hour hand |
| 09P85MGH | others - hour hand |