Pandahall 1000pcs/box Red Copper Iron Open Round Jump Rings Close but Unsoldered Assorted Various 4~10mm Size Split Ring KeyChain Jewelry Makings 1Box Iron Open Round Jump Rings Close but Unsoldered Nickle Free Quantity: approximately 1000pcs,about 59g/box. Variety of sizes: about 4~10mm outside diameter, about 2.6~8mm inner diameter, 0.7~1mm thick. Open round jump rings are an integral part of jewelry-making. They hold designs together and will allow you to embellish them in numerous ways. From adding charms to lengthening clasps, jump rings are always needed. These jump rings feature a versatile round shape and can easily be opened and closed with chain nose pliers. Use it to attach a clasp to chain, create dangles and more. You'll love having this beading basic on hand for all of your projects.