The Phiten X-30 Titanium Necklace contains a higher concentration of AQUA-TITANIUM, which is water-soluble titanium produced through our Phild Process technology. The outer material is 100% Nylon, and the inner material is 100% elastomer with Compound Titanium. The Phiten X-30 Necklaces are made in Japan and distributed by PHI-TEN USA, Inc.;