CF Industries Holdings, Inc. is a manufacturer of hydrogen and nitrogen products for clean energy, fertilizer, emissions abatement, and other industrial applications. The Company operates nitrogen manufacturing complexes in the United States, Canada and the United Kingdom. Its segments include ammonia, granular urea, UAN, AN and Other. The Company's primary nitrogen products are ammonia, granular urea, urea ammonium nitrate solution (UAN) and ammonium nitrate (AN). Its core product is anhydrous ammonia (ammonia), which contains 82% nitrogen and 18% hydrogen. Its nitrogen products that are upgraded from ammonia are granular urea, UAN and AN. Its other nitrogen products include diesel exhaust fluid (DEF), urea liquor, nitric acid and aqua ammonia, which are sold primarily to its industrial customers, and compound fertilizer products (NPKs), which are solid granular fertilizer products for which the nutrient content is a combination of nitrogen, phosphorus and potassium.