These were used on my RatRig V-Core-3.1, 400mm, with 150N gas struts. It may work for other sizes and/or 100N struts, though positioning might be different.
You will need:
I couldn't get the recommended configuration to work from the instructions, even with the more-powerful 150N struts that came with my V-Core-3 kit a few months ago (normally 100N). The goal was to find a positioning where the strut is mostly pushing horizontal when closed, vertical when open, and far enough back that it could push the lid wide open with its limited length. I felt the only way to get that was to elevate the bottom end of the strut, and have it pushing towards the back of the printer
The easiest way I found for installing the struts (in general, not just with this mod) is to have a second person hold the top open to the desired position (or find a stable way to prop it open), then install the struts in the fully-extended position. However, BE CAREFUL the first time you close the lid, If you did it wrong, the fully-closed position is shorter than the strut and something will break (strut, mount or frame)
This struggle made me appreciate why the default V-Core-3.1 enclosure is not great. I wish I had gone with open-front mod or the Enclosure 2.0 kit (released shortly after I finished my build). I highly recommend doing that instead if you haven't built the printer yet.
The author hasn't provided the model origin yet.