stages power meter, which crank arm do they use?

stages claim that their product add only tiny bit of weight to stock crank arm (15g?)

I’m looking for sram compatible ones.

And I think sram eagle sx/nx/gx/xx1 crank arm has different weight.

So my question is, which crank arm (among the sx/nx/gx/xx1) do stages use for their power meter?
(https://powermetercity.com/product/stages-carbon-for-sram-bb30-power-meter/)