Shortfill e-liquids are larger bottles of liquid in 0mg nicotine strength, including 60ml bottles that are only filled to 80% capacity, hence short fill. The remaining space allows you to add a 10ml nicotine shot or nicotine salt (or two) to boost to your desired nicotine strength.
After adding 1 nicotine booster to the 60ml shortfill bottle this makes it up to 3mg, adding 2 nicotine boosters will make it up to 6mg, simply shake the contents vigorously.
