I’m actually not sure where they source it from but my guess would be they just have an abundant stock of it given the abundance of everything else in the shop.

It’s black wax 5 hole paper tape and the controllers the use it are Allen Bradley, manufactured in early 80s I believe but I’d have to check dates.

We also have a few machines that read from magnetic tape so lots of old almost historical computer equipment, but still being used amazingly and making money.