When I worked at Apparat around 1981, we used a lot of *male* IDC edge card connectors. I've almost never seen any since, and I couldn't remember the name of the vendor. I just found out that it was Kel-Am, but the internet knows almost nothing about them.
Here's an example: https://www.elliottelectronicsupply.com/connectors/card-edge/male-card-edge-idc-connector-34-position-kel-am-idc34m.html That photo doesn't show the Kel-Am logo, which is just a stylized "KEL-AM". There are some eBay auctions of the corresponding female connector (which other vendors did make), some of which show the logo. I wonder what happened to Kel-Am. Maybe they were acquired, maybe they went under. It would be nice to find a copy of their catalog. Speaking of which, it would also be nice to see some Robinson Nugent connector catalogs from the late 1970s and early 1980s. I am especially interested in seeing specs for their bottom-entry square-pin receptacles, which I think _might_ be the ones used on Apple /// memory boards.