Chemically speaking, this molecule is "midway" amongst Sorbitan Oleate and Sorbitan Trioleate, that means that it's also an attachment of sorbitan (a dehydrated sorbitol (sugar) molecule) with the unsaturated fatty acid Oleic Acid, but in the ratio of 2:three hence the "Sesqui" part within the molecule's name. I also like that this is within a tub