2-in-1 Stackable Formula: Powerful Nitric Oxide & Test Amplifier America's #1 Selling Body Building Supplement♦ Hybrid Muscle Pump Formula & Powerful Test Amplifier Supports Nitric Oxide Production for Superior Muscle Pumps Increases Free Testosterone Stack With Your Pre-Workout or Testosterone Booster to Enhance Performance 1-Month Supply Dietary Supplement Hybrid Muscle Pump Formula & Powerful Test Amplifier SX-7 researchers have engineered a dual-function formula backed by real human clinical studies on its core ingredients. N.O.x. Test SX-7 Black Onyx is an intense nitric oxide and muscle pump inducing formula with the added benefit of boosting testosterone. Using studied key ingredients, N.O.x. Test SX-7 Black Onyx delivers a unique experience that is completely stackable with other pre-workouts or testosterone boosters. L-citrulline - An amino acid that is a precursor to arginine, shown to reach superior peak plasma arginine levels than a larger dose of L-arginine. L-arginine - An amino acid shown to increase blood flow and vasodilation to support muscle pumps. Quercetin - A bioflavonoid shown to increase key markers of nitric oxide production and reduce a vasoconstricting factor. Red Wine Fruit Extract - Supplies proanthocyanidins - a key polyphenol - which emerging research shows may support the production of nitric oxide. Boron - Shown in human clinical research to increase free testosterone and decrease estradiol in just 7 days. Free testosterone is the most bioavailable form of testosterone and supports the musclebuilding process. Rhodiola crenulata and Ginkgo biloba - This combination of ingredients has been shown in a human clinical study to maintain peak testosterone-to-catabolic-hormone ratio and enhance performance. Brassica oleracea and Bladderwrack extract - Supplying diindolylmethan and fucoxanthin. Stack with Test 3X SX7 Black Onyx for synergistic effects and maximum results! ♦ Based on AC Nielsen FDMx sales data for Hydroxycut caplets.