The EMIT for Cannabinoids has a cutoff range of 20 ng/mL. The exact specs I get get later. I, in my experience with this test, have found it's result questionable. I have compared results with a quantitative RIA and found many indiscressions. I trust RIA values much more. I'll see if I can find more info, if you want. Corey W. Stradling Aelfweald at aol.com