Wholesale Prices in Price Matrix, Jump Rings Jewelry Findings are Sold by the 1/2 pound bag - there are approx. 5,000 pieces. These are made from Heavy duty Stainless Spring Steel that has been electro plated with real silver. The wire gauge size of both rings are just a little less than 1mm (.74mm) The 4mm size jump rings are 4mm in diameter from outside to outside of ring. The inside diameter is just a little over 3mm from inside to inside of the ring. The 5mm size jump rings are 5mm in diameter from outside to outside of ring. The inside diameter is just a little over 4mm from inside to inside of the ring. Perfect item for your jewelry and craft needs.