Integrating One-Shot S4303 J system building block
The board has various passive and active components, which are surrounded by an aluminum frame and a blue plastic 22 pin male connector. On the solder side there is a grid lettered A-Z. On one side of the frame there is a green "Approved" sticker. on the other side there is a large yellow tag with the model number and the date 11/11/63.
Digital Equipment Corporation (DEC)
Printed on the solder side near the insertion end.