I have the QF Brawler Race 850 and one of the floats is Nitrophyl and the other is brass too. Which is weird. I bought mine in 2020 when parts were scarce.
Mine too.(850 brawler race also)
Edit: they use the nitrophyl in the rear cause of the jet extensions. In the front, no extensions, so no need for the nitro, so you get brass.