38% Phosphoric Acid Etching Gel Dental Etching Gel 37% Phosphoric Acid For clinicians who prefer a creamier gel that readily settles into dentin and enamel, but does not run, Etch Royale is the perfect choice. The darker blue color is easier to see in thin applications. Etch Royale has all the same features as Etch-Rite�, but the consistency is slightly creamier than its famous sister product. Creamier Consistency Darker Blue Color Packaging: 2 x 25ml syringes