Island Fog and Boink eJuice comes in 3 nicotine levels in the 70VG 30PG line (0mg ,3mg,6mg). We also offer custom nic levels to suit your needs and device. Our nic salts come in 12mg, 24mg, 36mg and 48mg.
The level in short is the amount of nicotine in milligrams for each millimeter of eLiquid expressed as mg/ml. Some eLiquid companies represents their nicotine content as a percent per solution such as 1.2% instead of 12 mg/ml. These technically mean the same thing however interpreted differently.