We've fallen in love with the beautiful and easy-to-use chain maille supplies by Weave Got Maille. These 18-gauge jump rings with a 3.5mm I.D. (inner diameter) and 5.6mm O.D. (outer diameter) are a great size for learning to make the byzantine weave. Made in the USA, these enameled copper jump rings come in a stunning array of brilliant colors that are durable and more reliable than anodized colors. Jump rings sizes follow the American Wire Gauge (AWG) system of measurement, sometimes known as the Brown and Sharpe (B&S) system. All enamel colors are tumble polished to give them a bright and shiny appearance.