What is it?Precision Engineered Nutrition L-Arginine provides 500mg of Arginine in each capsule. L-Arginine is a non-essential amino acid which means it can be produced by the body as well as obtained through the diet.Each Capsule Contains 500mg of L-Arginine Amino Acids are the Building Blocks of Protein What Are the Benefits of This Supplement?Amino acids are the building blocks of protein. Protein makes up the structure of all cells and tissues in the body, including muscle tissue, tendons, internal organs, skin, hair, and nails. There are 20 amino acids, 12 of these can be made by the body and are referred to as non-essential, whilst the other 8 are known as essential and can only be supplied by the diet. Foods such as soya, chicken and beef are good sources of Arginine. You must be 18 years or older to purchase this product.