Alcohol is a powerful substance. It's like liquid fire-- the ultimate destroyer. It can destroy any bacteria, virus, or microorganism. It can destroy any hope you had of a functioning relationship after you make out with a DJ in Kansas City. But most relevant to you now-- it can destroy resin and build up in your glass pieces. 

In the store, you usually buy 70% or 92%. If you ask them if they have 99% pure isopropyl alcohol, they will burn you at the stake for practicing witchcraft. Not at Smoke Cartel.

99% provides many advantages. Not only will it scourge the caked gunk that plagues your beautiful piece better than watered-down solutions-- the high concentration makes for much quicker evaporation.

The choice is clear. Just try not to smell it.