ROOT

What is the shlef life for flavor concentrate? Will the flavoring spoil?

What Does %PG/%VG Mean?  how to choose?

E-liquid is a mixture of varying amounts of about 4 different ingredients.  Water, Nicotine, PG (propylene glycol) or VG (vegetable glycerin) and flavoring.  Some liquids can have additional ingredients, but for the most part, these are the main ingredients to all e-liquid.

The amount of nicotine is dependent on the strength of nicotine in your e-liquid, but let’s say it is around 10% nicotine.  Somewhere around 10% of your e-liquid will be flavoring. And depending on how you like your vape, that determines the percentage of PG and VG in your e-liquid.

I had a small conversation about this awhile back in a thread, but I wanted to get a larger consensus of the community.
So, the question I propose: What, exactly and specifically, makes a mod a "mechanical" mod?
Two definitions I've seen people use:
1. No circuit board, just a straight voltage device, with a switch. The construction of the switch and wires doesn't matter.
2. No wires, no factory-produced switches.