No longer.It used to contain an auxin I believe can't find my old bottle, PGR. Vitamin B1 is made by the plant, It's uptake can not occur on a cellular level.
The only Plant Growth Regulator that I endorse is Triacontanol and has to be purchased from laboratories in States., I've run 12-14 week haze hybrids and cut them down maybe 2 weeks indoors. It takes a bit to mix it, not water soluble and a foiler spray weekly, under leaf best, is adequate. Once mixed it has a short shelf life. Mixes with Propylene Glycol 15.
Paclobutrazol is a PGR that is POISON, what they spray power lines with, and makes bushes and rock hard buds, Google the brands. Unfortunately, it is not regulated and if you use it or prefer bushes and rock hard buds, I'm sorry for you.-bk