Look at the color: In the absence of nicotine, e-liquid is generally colorless or light yellow.thin disposable vape, If you add some heavy color extract, there will be corresponding color, if you add nicotine or add too much natural extract, the coloring will be more unstable
Sense of smell: The first sense of smell should not be unpleasant, you may not like the smell, but it should not feel unpleasant and repelling, with the exception of fellow females, especially tobacco or nicotine.
Look at the amount of smoke: The amount of smoke is not only related to the quality of the atomizer, but also has a lot to do with the e-liquid. The smoke oil with a large amount of smoke is better than the small smoke, easy to smoke, and the smoke taste is delicate and moist.
like:
Electronic cigarette short circuit protection released
How to Blow Smoke Rings and Jellyfish with Electronic Steam
What exactly is an electronic cigarette in the eyes of players
The Wall