This is a pistol brace that is similar to a Flux style blade brace but works on a Sig folding brace arm that has a Gear Head Works adapter mounted to it. This is press fit on and is a snug fit.
Simply use pliers to grip and unscrew the stock spinning brace from the Sig folding arm. Replace with the Gear Head Works adapter and snug that into place.
The brace blade is best printed with the text face down on the print bed. The bore includes a key to stop this blade from spinning as well. When you install the Gear Head Works, ensure there is enough space in the adapter to fit the printed key feature.
This is press fit and best installed on a sturdy surface with a soft mallet tapping it into place.
You need the below two items to work with this printed brace arm.
Sig PCB Folding Brace:
https://www.sigsauer.com/sig-sauer-folding-pcb-kit-mpx-mcx-black.html
Gear Head Works Adapter:
https://gearheadworks.com/product/tailhook-adapter-to-fix-sig-spin-brace/
The author marked this model as their own original creation.