Boost is an optional selection that we offer to our customers. It's a way for you to add additional flavor to your bottle of e-liquid but is not required.
For example, if you like Green Apple but desire a stronger taste, then you could add boost to make that flavor more pronounced. We'd recommend flavor boost on some fruits, drinks, candy, and desert flavors, however we would strongly suggest not adding boost to menthol or tobacco flavors. If you are concerned or confused, we ask that you order smaller bottles and see what you prefer before ordering larger bottles.
Remember that flavor is subjective and what may taste wonderful to you may taste awful to someone else.