Jump ring opening tools, each internal diameter is about 17 mm/ 0.67 inch, external diameter is about 20 mm/ 0.79 inch, and approx. 7.8 mm/ 0.31 inch in width; Suitable size to meet your different needs in working and daily life the opening closing rings tools are made of stainless steel material, durable and sturdy to use, not easy to break or deform, resist rust and corrosion, can serve you for a long time; Lightweight for you to carry and store, bring you much convenience each stainless steel jump ring opener is designed with 4 grooves, easy for you to open or close the jump rings; You can also wear it on your hand as a decorative ring, and the chic design will bring you an exquisite effect the circle jump ring tool is an important tool for you to do some making and repairing projects in your daily life, will bring you much convenience, and practical for you to apply you can apply the jump ring opening tools on different projects, such as jewelry making, jump ring opening and closing, necklace repairing and so on; You can also match the ring with your other decorative accessories, making you stand out in crowds