When the TPD regulations came into effect in May 2016, this caused a big shakeup in the way e-liquids would be able to be sold.
Long gone are the days of buying any bottle size containing the nicotine strength you required, and this was due to the restrictions on the sizes of e-liquid bottles. The bottles that could be sold with nicotine-containing e-liquid were limited to only 10ml in size and the nicotine content was also restricted making the highest dosage of nicotine 20mg (20mg/ml).
The good news is this saw the beginning of short fill bottles of e-liquid. As the bottle size was not limited for bottles containing nicotine free e-liquid this meant that companies were able to produce the same (if not more) e-liquids but all in bigger bottles. The size of the short fill bottles would differ, company to company but the one thing that stayed consistent was the nicotine that had to be 0mg/ml.
So, the term "short fill bottle" related to the larger bottles of e-liquid which you still see available today. Usually, the sizes of these bottles would be either 30ml, 60ml or 120ml. All of the liquids that come in the short fill bottles would appear to be missing a little bit of e-liquid, but this is intentional. Leaving space within the bottle would allow the user to add “nicotine shots” themselves (if required) to reach the nicotine strength preferred.
Nicotine shots / Nic Shots also became a staple product within the market, as most e-cigarette users tend to use e-liquid with nicotine.
How to Mix
The way to mix the e-liquid and nicotine shots together is clearly shown on the image below and the process is very simple to do.
To add nicotine to a short fill bottle, you would need to remove the lid of the bottle followed by the inner top cap. Then add your nicotine into the bottle and once this is added you can pop the top cap of the bottle back into place, ensuring it is fitted back correctly, put the lid of the bottle back and then shake the bottle. Shaking the bottle for roughly a few minutes will mix the nicotine solution with the e-liquid.
As you can see, if there is 50ml of e-liquid in a 60ml short fill bottle then there is 10ml of space where you can add a full 10ml bottle containing an 18mg nicotine shot, thus giving you 60ml of e-liquid with a 3mg nicotine content once mixed together.