King Koe 8mm High Polished Center Matte Finish Men's Tungsten Ring Wedding Band Comfort Fit Pass ASTM F2999 test. What is ASTM F2999? ASTM International approved ASTM F2999, Standard Consumer Safety Specification for Adult Jewelry. The purpose of the standard is to establish nationally recognized safety requirements and test methods for adult jewelry, including lead content in base materials, heavy metals in surface coatings, and cadmium in certain substrate materials. Because the rings pass ASTM F2999 test, really hypoallergenic and health. Test report shows on the left pictures. ASTM is the abbreviation for American Society for Testing and Materials. ASTM International is a globally recognized leader in the development and delivery of voluntary consensus standards. Today, over 12,000 ASTM standards are used around the world to improve product quality, enhance health and safety, strengthen market access and trade, and build consumer confidence. Six-Months money back guarantee or exchange. Life time warranty! Made of genuine tungsten carbide. scratch resistant, durable. 8mm Matte Finished Tungsten, great as a wedding and engagement ring for men. High Polish Smooth Inner Face, Comfortable Wearing. The smooth and gentle contrast of the polished beveled edge and the satin/brushed finish center is exquisite. All rings come with Ring Box, save your gift-wrap fee, and help you store the ring.