L-Arginine Free Form 1000mg - 200 TabletsSource Naturals L Arginine Free Form provides 1000mg of crystalline, free form L Arginine per tablet. This essential amino acid is presented in its most bioavailable form for optimal absorption and utilization by the body. The free form designation means the amino acid is in its pure, unbound state, ready for immediate use. L Arginine plays an important role in muscle metabolism by helping to transport, store, and excrete nitrogen throughout the body.