The ultimate NEW AND IMPROVED superblend of frankincense, utillizing premium grade resins from Boswellia carterii, Boswellia sacra, Boswellia serrata, Boswellia neglecta, Boswellia papyrifera and Boswellia frereana. This blend is very similar to a quad blend Dr. Pappas formulated a number of years ago and used by some big name brands, but now it contains MORE premium grade resins of frankincense and is deeper and richer due to the proprietary distillation process developed at Essential Oil University.