This is a cap for memory sticks. There is a key-chain loop attached. The usb key fits all the way in.
I printed this with the Anycubic i3 Mega, at 0.06 mm layer height. It may need supports on the inside. I used "line" supports and pulled everything out with tweezers.
It fits the USB tight so you might want to push one in hard and pull it out a couple of times before regular use. If it printed correctly you should be able to push the USB all the way inside.
I used AutoCAD to draw the design. I made measurements using a caliper and made several prototypes and tweaks to the design before it was perfect.
I am a student studying engineering. If you would like to help support me and my projects please feel free to donate. I hope you find use in my designs.