20 gauge Natural ID 3/16 inch. Inner diameter: 3.57mm. Outer diameter: 5.19mm. Made from Artistic Wire, these jump rings are precision cut and system matched for diameter and color consistency. Accurate inside diameters retain design aspect ratios, plus the consistent shape of these rings help maintain a uniform geometric weave. Rings can be opened and closed using the regular or bent Chain Nose Pliers. Pack of 180 pieces.