Perfectly snug fit for my USB battery pack. Not sure what others it will hold, but it holds this Lekzai one like a glove: https://amzn.to/3nZFsgh (affiliate link)

Let me know in the comments if there are other very common battery pack sizes and I'll add some versions.

Print Settings:

• Layer Height: 0.28mm (or less)
• Filament: PLA
• Infill: 15%

For the full video of my HSW wall check it out on the Fix This Build That YouTube channel: https://youtu.be/NsBqs3TRjqQ