Planetary Herbals, Cat's Claw, Una de Gato, 750 mg, 90 TabletsSupports Natural Defenses Herbal Supplement Approved by Michael Tierra L. Ac, O. M. D Cat's Claw (Uncaria tomentosa) is a woody vine that grows in the Peruvian Amazon rain forest. Indigenous people have utilized this renowned plant for hundreds of years. Planetary Herbals Cat's Claw uses only the inner bark of the above ground vine, which preserves the root for future growth.