Vape E-Liquid, a key component of electronic cigarettes/atomizers, usually includes nicotine, flavorings, and other base ingredients. When choosing atomizer e-liquid, you will usually encounter two different types of nicotine e-liquids: freebase nicotine and nicotine salts. These two types have different properties and applications and are suitable for different types of atomizer devices.

** Freebase Nicotine:
Introduction: Freebase nicotine is the traditional form of nicotine extracted from tobacco and has been widely used for a long time.

Features :
- Higher pH, resulting in throat irritation and a slightly harsher smoking experience.
- Nicotine is absorbed more slowly and requires more time to satisfy nicotine needs.
- Suitable for use in high power, low resistance Sub-Ohm devices as they are able to generate enough heat to effectively vaporize free nicotine.

** Nicotine Salt:
Introduction: Nicotine salt is a relatively new nicotine e-liquid formula that has gained popularity in recent years. It is a modified form of nicotine that is naturally derived from tobacco leaves.

Features:
- Typically lower pH, providing a smoother and less irritating throat sensation.
- Nicotine is absorbed faster, providing a quick nicotine replenishment similar to the feeling of smoking a traditional cigarette.
- Suitable for use in low power output MTL (mouth-to-lung) devices which are well suited to the higher nicotine concentrations commonly found in nicotine salt e-liquids.

Difference: The main difference between free nicotine and nicotine salt e-liquids is the speed of nicotine absorption and throat irritation. Free nicotine takes longer to reach peak blood nicotine levels but provides a stronger throat irritation. Nicotine salts, on the other hand, provide a fast nicotine release with a lighter throat sensation.

Recommended equipment:
Freebase Nicotine Liquid: Suitable for use in Sub-Ohm devices, which usually have higher power output and are able to generate the required heat to effectively vaporize free nicotine. (such as SMOK / GEEK VAPE)

Nicotine salt e-liquid: Best used in MTL devices, which have lower power outputs and are well suited to the higher nicotine concentrations commonly found in nicotine salt e-liquids. These devices are able to simulate the smoking experience of traditional cigarettes. (such as SMOK / UWELL)

Ultimately, the choice of free nicotine or nicotine salt e-liquids, and the type of device to use, should come down to personal preferences and needs. Whatever choice is made, one should be aware of the health risks associated with vaping and follow relevant safety and health guidelines.