They claim 1.o just above 1.0mL, 1.2mL... What I used to do was just add my own bac.. Keep in mind that after you mix the geno it will be about 2.14/2.15 ish, that's because the HGH has a 0.15 volumetric displacement..So it's safe to say that the amount of solution is near 1.0mL