This is very useful tool if you have hundreds or thousands of used tubes. I have a big quantity of rare used tubes and it was a nightmare when I need to put on tester tubes with bent or twisted pins. It happens to brake glass envelope where pin is entering the tube and when it happened to me with Telefunken’s ECC802S it was time to have this tool. Ebay didn’t exsist 20 years ago and I couldn’t get any NOS straightener tool, the only way was to make it in friend’s metal workshop.
It’s made for Miniatur, Noval, Decal and Magnoval socket, I still regret that there isn’t Rimlock socket which I was ordered, but my friend forgot to make it, and all job was done for free so I couldn’t complain … Don’t look a gift horse in the mouth …
ECC81 12AU7 Philips flat foil D getter with pins perfectly straightened on tool, no more nightmare during testing, they slide in socket like a charm
Even with this tool, pin straightening is risky sometimes, so my advice is to first use nose pliers to do pre straighten on extremely bad pins, sometimes it is even necessary to heat the pins before!