Approximately 39x10x3mm gunmetal plated base metal hinged donut bails for jewelry making. These bails have a 26mm inner diameter, and are easy to open and close. Plated over zinc. Fits up to 3.2-3.6mm chain or cording. For use with 50mm round gemstone donuts up to 7mm thick. Black gunmetal color may range. Once the interlocking loops are strung onto chain or cording, the donut is securely locked.