5.5mm x 3.8mm Box Rolo (Bicycle) Chain. Sold by the foot. CH133 Box Rolo chain is sometimes also referred to as bicycle chain. The 5.5mm x 3.8mm alternating vertical and horizontal links make this the ideal chain for necklaces, bracelets, and anklets. It is made from marine grade 316 stainless steel which is strong, durable, and resistant to rust corrosion and tarnishing. Use this chain if you wear religious or medical symbols that you prefer not to remove from your body. Dangle your favorite pendant, charm, bead, or baubles from the open links. The stainless steel silver color will complement any color palette. * Sold by the foot. * Made from 316 stainless steel. * 100% lead-safe. Super fast shipping for USA customers. Hurry while supplies last!