If you know what these boards are from email me at djg@pdp8online.com

Date codes of 1964. Size 4.5"x3.25". Looks like used card edge for
keying but has separate 23 pin connector for electrical connection.
No useful markings I can see. Has card ## on the back.

The connector pins seem to match other General Electric (GE) computer
boards such as the 225 series but bords are not an exact match.

http://ed-thelen.org/GE-225-Boards-Heinzen-.html