UPDATE : I passed my most recent 4 panel d test with QF PLUS 6.4 but it’s been a journey so as u can see in the picture I posted with this post 2 different labels & QF’s the one on the right came up inconclusive at my first concentra d test about 2 weeks ago & the lady at concentra didn’t sign my papers properly because so . So BEWARE OF FAKES the fake had a verifiable batch number n all .i took another 4 panel d test on Monday this week got results by next morning n job start date next week all is clear QF 6.4 Still works just gotta make sure its the official one u can see in the picture the differences & even the font on the bottles are different BEWARE but QF 6.4 still works 100% just make sure temp is correct & don’t overheat which can change nitrite levels .Hope this can calm some nerves because I was extremely stressed now I have a job position I’ve wanted for years over 100k club LETS GO GOOD LUCK TO ALL