THC:CBD Transdermal Patch from Pura Elements. The skin is the barrier that lies between us and our natural environments. As a protective layer, molecules such as cannabinoids are often too large to deeply penetrate the skin when applied transdermally – Pura Elements has developed a blended formulation using added plant extracts that increase the skins’ permeability in order to enhance cannabinoid delivery for maximum achievable absorption into the bloodstream (bioavailability). The patches provide discrete, slow-release administration of cannabinoids that maintain their medical benefit with minimal psychoactive effects, without the use of synthetic and potentially harmful chemical enhancers. Contains 20mg THC and 20mg CBD.