It says Ethyl Alcohol, which is often denatured. Not everyone uses the same denaturing agents.
However, in one of the comments he says:
"The one I use is Ethyl alcohol (pure 96%) also called Ethanol. It's the one used as antiseptic."
Medical Ethyl alcohol seems to be about 95% or so.
Hardware store denatured alcohol seems to be about 90%.
Some people in the comments mentioned Everclear. It seems to be sold in 75.5% (151 proof) and 95% (190 proof).
Steve Greenfield AE7HD