This Tungsten Forever celtic knot piece is right out of the pages of history. This traditional wedding design, a centuries old symbol of love and union, is now available within the most modern material available in jewelry, Tungsten Carbide. The Guinness has polished grooves on each edge, framing in the etching. We laser etch the ring twice to ensure maximum clarity, contrast, and quality. Lifetime Sizing, Lifetime Warranty, & Ships in 1 business day!