So, I can vape terpenes? I am so confused, how do I buy it? Is it legal?

Terpenes or terpenoids, the chemical category of the "essential oils" found in plants, carry the distinctive plant fragrances (like rose oil or orange oil). Cannabis, being very fragrant, is rich in these essential oils. In fact, these substances are bioactive and have been used in herbal remedies for generations. Proponents of the "entourage effect" believe they are an essential component in producing cannabis's effects, and are clearly important in giving different varieties of cannabis their distinct qualities. Little science is available to guide us in using terpenes apart from the way the naturally occur, as a component of the plant that produced them, although their toxicities (very low but greater than the cannabinoids) have been investigated somewhat. Subjecting concentrated terpenes to high temperatures and inhaling the result does not seem like a great idea (eg dabbing) because harmful compounds can be created by that process. But inhaling vaporized terpenes at a lower temperature is likely not much of a health risk, depending of course on how much it's being done and how the oil being vaped was created (you want to avoid solvent extractions). I believe some vape pen makers already add terpenes to their formulas. I am actually surprised that I haven't heard more about pure terpene vapes-there may be issues here I'm not aware of. I don't think there is any legal issue without cannabinoids. I will be on the lookout about this.