Derived from the amino acid leucine, HMB is a highly concentrated, proprietary breakthrough in muscle support and protection. Along with HMB, Bone and Muscle Defense also contains the patented nutrient OsteoSine®, to support healthy bones, and is rounded out with clinical dosages of Vitamin D3, a potent and patented form of K2 called K2Vital®, Magnesium, and L-Carnitine, for the most complete bone and muscle support formulation available today. Here at Green Valley, we only work with US-based manufacturing facilities that are cGMP (Good Manufacturing Practices) Certified and NSF and FDA inspected. Our products are triple tested to ensure potency and purity and are stored in our temperature and humidity-controlled warehouse right here in the Shenandoah Valley, Virginia. And we ship directly to your doorstep – we don't share warehouse space and we don't hand off your business to a third party to fulfill your order. Best of all, all Green Valley products come with our 90-day Satisfaction Guarantee.