This is an ethyl maltol (EM) , 10% PG based flavor enhancer.
Primarily it is a sweetener additive. Named as a flavor enhancer as it does a great job at boosting “thickness” in single flavors. Good for dessert based flavours and more!
 
Ethyl Maltol (EM), Unlike Sucralose, sweetens certain flavours such as non-citrus fruits. It helps to remove the tart element of strawberry, mango and blueberry and make them a small amount sweeter. 
 
Ethyl Maltol ( EM) is a popular enhancer. This is often viewed as a sweetener, but that would not be correct. Ethyl Maltol, or EM, is actually just a cotton candy flavored aroma. Because this is an aroma, it doesn't work on the sweetness receptors of tongue, and therefore not a sweetener. So don't use it like a sweetener! It is better to be used with custard and creams but not fruits, for frutis cap Super Sweet is the better choice. 
 
The sugar lips coming from some commercial eliquids is not coming from EM, so do not add EM to your ecipe to create a sugar lips sweet feeling, that sugar lips will be reached by adding Sucrolose (Capella Super sweet, or TFA sweetener).
 
So for fruits add Cap Super Sweet and for custards add EM.