Jewelers Jump Ring O Ring Opening Closing Repair Tools This is a new stainless steel linking ring This is extra handy for opening and closing jump rings of various sizes With a pair of chain nose pliers and a linking ring you can open and close jump rings with ease and accuracy without damaging other parts on necklaces, earrings, etc It is stainless steel and has 3 different size grooves to fit various jump rings It measures approximately 19 x 9 mm (3/4" x 3/8")