Jump Rings
Jump rings are available in two varieties: jumprings for general jewelry making, and jumprings for making Chain Maille. Jump rings for general jewelry making are oval or round and are measured using the outside diameter of the ring. Jump rings for Chain Maille are round and are measured using the inside diameter and the wire gauge used to make the jump ring.
Let's Bead! has a huge selection of jump rings made of sterling silver, pewter, jeweler's brass, gold filled, enamel on copper (in many colors), anodized aluminum (in many colors), copper, and niobium