This is a two-sided printed circuit board with edge connectors on both ends. Thre is one inspection stamp on component side, and one on the solder side.
Identifying Numbers
Other number
4
Hand-written on yellow label, component side, upper edge
Other number
4022 422 01004
Printed in metal, component side, lower left corner
Other number
PC1845/02
Printed in metal, component side, upper left corner
Other number
PR626
Printed in white, component side, upper right corner
Other number
WB 0900
Printed on white label, component side, upper left corner