PGA means pure grain alcohol (as in everclear) or it may be referred to as grain neutral spirits (GNS) some places. It also means Professional Golf Association, but that’s just a coincidence.
People use it to thin out high VG mixes that are having troubles from being too thick. You can use vodka instead of PGA. Or distilled water can do the trick too and doesn’t add the throat hit that alcohol has. Use anywhere from 0-5% depending on how much you need to get the desired result.
I use PGA- Pure Grain Alcohol. Used Vodka in the past but changed because PGA seemed to me not to be as harsh and zero flavor after breathing during steep process. However vodka cheaper.
You might consider distilled water (DW). It’s even cheaper, has no flavor, and adds no throat hit. 
I use vodka and distilled water to thin and break down the VG. (I use really expensive vodka).
I know it’s a bit early, but in anniversary honor of @Aux video suggested use of Vodka in relation to vaping… 
…there is a video in the link. 
Thanks old sport
That is the first I seen and it is hilarious !!!
Couldn’t help reviving that post from last year! 
But in all seriousness, I’ve used a bunch of PGA (not vodka…too much H2O in vodka) in my mixing over the last few months; NET and liquefying/reconstituting tobacco absolutes. It’s great stuff for such uses. A bit of an open container evaporation process is in store for those who don’t like alcohol in their mix.
Distilled water was never my friend in mixing… I found it had too much of a snap, crackle, and pop effect on my final product. 
…don’t like it when hot ejuice pops out of my RDA or RTA air flow intake holes and lands on my face or chest! Ouch! 
yea I have just about given up on DW in my mixes for that same reason…not fun at all and hurts it’s like pop rocks all over again and not in a good way!
Question for those that mix with PGA.
Do you keep your finished mixes in smaller bottles to prevent evaporation of the alcohol?
I’m thinking if I mixed 120ml, the PGA would be gone before the bottle is empty.
I make my 120 ml mix with PGA, when finished mixing and stirring with magnetic stirrer or frothers I leave my cap off for eight to twelve hours to breath. Some people use heat to help evaporation of alcohol. Also I’ve learned on mixes with 15% or more flavor never more than one or two percent PGA, flavor between ten and fifteen percent never more than three percent or else it will mute flavors. Rarely I have a five percent flavor mix and I’ll do five percent PGA. But will mute flavor. This is my way your way will most likely be different just have to play with it and figure out what’s best for you and your Vape style.
I recently bought some Everclear (I make my own Limoncello) …and it didn’t even have a childproof top! Just think about how many children are brought into this world because of PGA …is that Irony? Jokes aside, I suspect many premium juices have some added alcohol (and water) …is true?
Water I agree, alcohol too expensive. Cheap ass companies don’t want to spend that money. They just use heavy pg to thin. I love me some PGA in my mixes!!! Make it just right for my vapie vape Vape
@BoDarc Yes, many premium juices have alcohol and/or water. Incidentally, here in Florida it’s illegal to sell PGA.
Really! Damn state. They shoot shuttles to space but can’t buy PGA? Got to love the good old USA.
@Ggrhauling - Don’t get me started on Florida. People in New Jersey look at Florida and say, “Now that state’s corrupt”.
Doesn’t sound like the most inspiring competition, does it? LOL
I’m still trying to get over Flordia not selling PGA. We lived in Tennessee a few years and no liquor with in sixty miles of Athens Tenn. they called it dry county. Freaking had to go to a bootlegger.