Norvell is the largest purchaser of DHA in the entire world. We are a "true manufacturer" of all the products we sell. The term true manufacturer means we manufacture and control the production and formulation of our products from the beginning to the very end. With a comprehensive selection of tested and proven products that provide the best results in the industry, Norvell offers premium solutions and supplies that build customer loyalty. With Norvell's state-of-the-art handheld machines, leading solutions and arsenal of ingenious guns, you can customize sunless tanning results. When you apply Norvell sunless tanning products, you are adding DHA. The combination of the 3 - DHA, oxygen, and amino acids - begin a process by which the amino acids darken and a sunless tan is revealed. This development process can be influenced by several factors such as skin type, thickness, pH levels, medication, and dryness of the skin. Mastering these influences, Norvell has formulated recommendations, as well as a vast array of products to PRIME, ENHANCE, and OPTIMIZE a sunless tan from beginning to end. The day prior to a sunless tan application, one should begin readying the skin to achieve the best results. Exfoliating, to remove loose, dead cells from the surface of the skin allows sunless products to be applied to the freshest layer. In turn, this provides the ideal canvas for an even application and naturally prolongs the length of the tan. In fact, it is a best practice to never shower less than 4 hours before a sunless tan and to use a sulfate-free cleanser that does not strip the skin of its precious resources. The outer layer of skin where body oils, fatty acids, and amino acids dwell, requires time to replenish itself along with the body's natural moisturizers. Allowing this replenishment to happen will provide darker tanning results, as amino acids in the skin are what turn brown.