This is a battery mount for a CRKD Nitro Deck+. The ND+ is a Nintendo Switch controller/dock that you use in place of joycons that has quite a few great features like hall joysticks, remappable buttons, rear and side buttons, built in dock, etc. This 3D printed part mounts on the back via four screws and then you use a velcro strap to hold a power bank battery on. In addition, if you have a pair of XR glasses (I'm using the Viture Pro XR), you can use this along with Viture's charge and play adapter (works with Viture glasses, I don't know about other makes/models), to play your Switch handheld with the XR glasses. For this to work, you need to supply power to the ND+'s USB-C input, AND to the Viture adapter's USB-C power input, and then plug the glasses into the other adapter's port, and finally, the adapter into the ND+'s USB-C output port. Check the pictures and you can see how it's connected.

This mount was designed for and around this power bank:

https://www.amazon.com/dp/B09VP41M71?th=1

Which is 2.6" x 2.6". If you want to use another power bank that doesn't fit to your liking, I've uploaded a step file that you can use in a variety of 3D editing programs, such as Fusion 360 to modify it to your power bank.

After printing, remove the four rear screws of your ND+. You will then need to use the two bottom (longer) screws you just removed to attach the printed part to the top screw holes. For the bottom holes, you will need #2 x ½" self-tapping screws. I used these:

https://www.amazon.com/dp/B0CCRT2YNN?th=1

Here is a link to the velcro straps I used, they are just under an inch wide, and I'm sure a variety of similar straps would work.

https://www.amazon.com/dp/B08HLJMMRC

I tried a variety of USB-A/C adapters, short cables and came up with the solution as in the two back pictures of the battery mounted, and the battery mounted with the Viture adapter.  These are the adapters/cables I used:

USB to USB C Adapter 3 Pack, 90 Degree USB C Female to USB Male Charger Converter

https://www.amazon.com/dp/B0CQCCDYVX?th=1

USB C Right Angle Adapter

https://www.amazon.com/dp/B08TZY4MSR?th=1

Futurizta Tech® Zeus-X Short USB-C to USB-C Cable 2 Packs (0.33ft/0.1m)

https://www.amazon.com/dp/B09Q9CWBBS?th=1

If you come up with something better, post pics links please but this has been pretty clean.