jibbs wrote:...I can't really find a definitive answer as to whether it is pure heptane or not...
When in doubt, look up the SDS [MSDS] for a product.
Take a look at
This One as an example.
You just scroll down to the components or composition section to see whats in the stuff.
Its best to read the most recent SDS you can find, in case the formula has changed over the years, but bestine never has. Its essentially pure heptane.
Now take this knowledge and apply it to other products with vague ingredient labels. I've found good sources for chemicals where the chemical was only listed in the SDS, and not on the product label.