This is a Sanlaki F8 print. It was designed with a lot of feedback and iterations with the discord. If anyone would like to get one of these there is a promotion through the game:
5% off gets applied at checkout automatically with code: 11SANLAKI

if you want to print it out yourself Sanlaki has also pasted it to thingiverse

I'd strongly suggest using it with something likethese batteries

these battery adapters

this velcro strap (you may need to cut it down)

or velcro strap from EU

also play without the battery lid (another -7g or so)

move the controller stap to sit like this for safety

and here is a close-up of how it the velcro sits

and as always, if you have any questions, reach out to me (discord is best)
via email:

via discord chat: (i'm carrotstien there)

via facebook chat:

instructions on how to select the appropriate preset:
Eleven Paddle Preset Installation Instructions

And here is a video of how you install the controller into the adapter:
Sanlaki Installation Video