See this at: thecarbideringstore....| Added on 07/04/08

Nickel-binder alloys. We start with the finest, purest tungsten and carbide powders purchased from reputable US metal suppliers. We utilize only nickel-binder alloys—not pure tungsten (which lacks hardness in its pure state) and not cobalt (which can... See more

Nickel-binder alloys. We start with the finest, purest tungsten and carbide powders purchased from reputable US metal suppliers. We utilize only nickel-binder alloys—not pure tungsten (which lacks hardness in its pure state) and not cobalt (which can react with your skin and produce a rash or permanently discolor your ring). Nickel-binder alloys are superior because they preserve the unique wear properties of tungsten and carbide and they’re also hypoallergenic: they’re chemically inert, won’t oxidize or irritate your skin. Made in America. Our tungsten carbide rings are manufactured exclusively in the United States to the highest quality standards. Comfort fit. The addition of extra metal on the inside of our rings gives them a slightly domed shapes—resulting in an extra comfortable fit. Lifetime warranty against manufacturing defects. If your tungsten carbide ring should ever fail structurally, we’ll replace it free of charge. Lifetime, unlimited sizing. Unlike gold, silver and... See less