ARTHRO KINETIC is a complex connective tissue maintenance support formula based on our 12 component matrix that includes more special ingredients in addition to the most common ones. (This is almost the same product, as Muscle Army Heavy Duty was before) NEM Natural Eggshell Membrane is a trademarked ingredient for these types of products. Arthro Kinetic also contains the preferred Type II Collagen, plus Hyaluronic Acid! Of course Arthro Kinetic provides the popular Glucosamine, Chondroitin and MSM as well. The 100% recommended daily amount Vitamin D contributes to the normal function of the immune system and muscles, and also to the maintenance of normal bones, teeth, and to the normal absorption/utilisation of Calcium and Phosphorus. Vitamin C helps to protect the cells from oxidative stress and contributes to normal collagen formation for the normal function of cartilages, bones, blood vessels, gums, teeth and skin. It also contributes to the normal function of the immune and nervous systems, and to the reduction of tiredness and fatigue. Zinc contributes to the maintenance of normal hair, nails, skin and normal vision. It also contributes to the maintenance of normal testosterone levels, to normal fertility and reproduction, and to normal protein synthesis. Manganese contributes to the normal formation of connective tissue.