Section 19.391 - Mixing denatured spirits(a)Spirits of the same formula. If a proprietor has two or more different batches of denatured spirits produced under the same formula, the proprietor may mix them on bonded premises.(b)Spirits of different formulas. A proprietor may mix denatured spirits produced under different formulas on bonded premises for immediate redistillation at the same plant or at another plant subject to the provisions of §§ 19.314 , 19.315 , and 19.316 .