These Brand New Miami Cuban Chains are 100% GENUINE, SOLID 10K YELLOW GOLD and have been professionally tested and stamped 10k. These chains are REAL SOLID GOLD, they are NOT HOLLOW, NOT PLATED, NOT FILLED. The chains fasten with a 10k Yellow Gold Double Safety Box Clasp that is durable and secure (the 4.5mm and lower sizes feature a lobster clasp). They can be layered, stacked, worn on their own or with a pendant or charm. Miami Cuban Chains are especially known for their classic style, shine, and strength. These high quality chains will not tarnish or discolor as they are Pure 10k Gold and MADE IN ITALY.