NKTR Sour is a sister company to NKTR Vapor-Liquid. If you liked the original flavors, but want a little more zing in every hit, then we highly recommend the Sour edition. Before we jump into the flavor descriptions, one of the most important things we need to mention about NKTR Sour is that they utilize Tobacco Free Nicotine aka TFN. Almost every e juice brand uses nicotine that originates from the tobacco plant. The nicotine is extracted from the tobacco plant and altered into a form that can be mixed into an e liquid. TFN, however is nicotine that does not come from a tobacco plant. It is 100% tobacco free and is made synthetically in a lab. TFN provides for stronger flavoring, a cleaner hit, and a smoother throat hit. The original NKTR brand was one of the first to utilize TFN, and it is one of the reasons why their e liquids are so incredible. Just like the original, all of the NKTR Sour e juices are simple single fruit flavors. In order to spice it up, they added a sour sugar accent to each one, which makes these flavors awesome. There are 3 premier flavors as of now, Watermelon, Strawberry, and Apple. Upon inhale of these flavors you will notice the fruit profiles, followed by the sharp notes of the sour sugar notes. They almost taste like sour hard candy. They are really really incredible. A Lot of sour flavors can have a throat hit that is a little harsh, NKTR Sour doesn't have that problem. All of their flavors have a smooth throat hit that apply a very small throat tickle. We carry NKTR Sour in 0MG, 3MG, and 6MG nicotine levels in 30ML bottles. They come in a white box with a big color splatter on them which matches the flavor profiles. Overall, NKTR Sour is by far one of the best sour e juice brands we carry. You're not going to want to miss out!