NOW Foods TestoJack 100 is a comprehensive herbal formula designed to support healthy testosterone levels, vitality, and male reproductive function using a synergistic combination of botanical adaptogens and nutrients. The formula features Tongkat Ali (Eurycoma longifolia) root extract — the most clinically researched herb for testosterone support — alongside Maca, Tribulus terrestris, American ginseng, and zinc. Tongkat Ali has demonstrated in multiple randomized controlled trials the ability to support free testosterone levels, improve muscle strength, and enhance libido and mood in men with low testosterone. The complete formula addresses multiple aspects of male hormonal health including stress (via adaptogens), reproductive function, and energy. Manufactured in NOW's GMP-certified facility with standardized herbal extracts for consistent potency.