This is a beautiful reproduction of antique book chain. Two different link styles in an alternating pattern. The first is an oval with a ball soldered on at the widest points where it measures 12mm. The other link is a flat band with a delicate embossed pattern and measures 5x7mm. It's open design makes it very lightweight for such a large chain. Lead & Nickel Free. Our basemetal chain is sold by the foot. We do our best to ensure all lengths of chain are one continuous piece whenever possible. Made in the USA.