I thought I'd be able to easily find what I want in a SD/miniSD/USB holder already here, but I really couldn't. I wanted one that mounted vertically on a surface, and was moderate size. I wanted it to take wide usb devices. I wanted it to be easy to remove cards. I wanted slots to be angled from vertical so cards wouldn't work themselves out of their slots with vibration. I also wanted a STEP file so I could make minor mods and remix.
I've included a version without the screw holes and without the angled back which works nicely on horizontal surfaces.
As an aside, why do so many people only post stl files? They are useless for remixing. Let's all do each other a solid, and post step files and if possible, original cad files. Like this! https://a360.co/2Ic5RPW
The author hasn't provided the model origin yet.