Nic shots are perfect for use with short fill e liquids. The Nicotine shots come in a 10ml bottle with a nicotine content of up to 20mg/ml and the usual nicotine dosage within these would be 18mg/ml. The easiest way to increase nicotine in a short fill e liquid bottle is to add the full 10ml of nicotine solution which will raise the content of the e-liquid from 0mg of nicotine to 3mg and will also increase the amount of e-liquid from 50ml to 60ml. If you use a larger bottle of e-liquid, i.e. 100ml then you can add 2 nicotine shots to reach the same result. There are two types of nicotine one being Salt Nic and the other being the Traditional Nicotine Booster. Nic Salts get absorbed into your blood stream quicker giving an instant nicotine sensation and is smoother on the inhale. A traditional nicotine shot takes longer to be received into your blood stream and can be more harsh on your throat on the inhale. Salt Nic is growing in popularity and many people now opt for this as a preference over traditional nicotine shots.