This classic 18K white gold filled herringbone chain necklace is 18 inches long and fastens with a lobster clasp. The chain is approximately 4mm wide. This necklace is nickel and lead-free. It is waterproof, so do your daily routine without having to take it off. Shower with them or take a swim. We have 16 inch ~ 38 inch; 18K White Gold/Yellow Gold Filled in stock for this model.*** Free Velvet Gift Pouch Included. .