Why this ring?It is not a plaything.It is heavy, hard and industrial.It relis on you and you can rely on him.It is made of the METAL FOR MEN.Tungsten carbide is tough and about 10 times harder than 19K Gold, four times harder than titanium, twice as hard as steel. It is so hard that only diamond can be used to cut it. Its density, similar to that of gold, allows tungsten to be used in jewelry as an alternative to gold or platinum. Is the only rare and exotic metal that can be permanently polished.The ring has a brushed finish in the center band and smooth polished beveled edges. It is the most incredible product we have ever created.Component List:Tungsten Carbide-----85.7% Ni-----9.5%(Nickel Release 0.26 microgram/cm2/week, completely meet the standard of EU Nickel Release Directive 2006/96/EC)Ta-----1.8%Ti-----1.5%Nb-----1% Cr-----0.3%others-----0.2%Caring Tips:1. Clean the ring with warm water and mild soap (no detergents).2. Tungsten carbide is a very hard and dense metal with hardness between 8.5 and 9.5 on the Mohs Hardness Scale (diamonds are a 10 - the highest). However, metal with extremely hardness usually with certain degree of brittleness. Your ring should never be tossed or impacted violently.3. Avoid exposure to chemicals and keep it in your TAN'S gift box when you are not wearing it.About TAN'S: TAN'S aim to create jewelry that never fades charm. We hope you can recall your beautiful memory when you touch your shining TAN'S ring after decades of years.