Naptha is a very general name.And chances are that the naptha you use is more than likely heptane with fractions of hexane.Not all brands of naptha are the same.The brand I use is called Rechochem Camping fuel and it is almost pure heptane with fractions of hexane.I hear that the "Ozark Trail" brand from Walmart is a good one but I never tried it.Just look up the MSDS sheets for whatever brand you plan on using
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