This Gold Filled chain is great for use as necklace extenders, because the larger loops are just the right size to fit a 10mm Lobster clasp (shown in picture). It also is a sturdy, closed loop chain, so you'll like it for other jewelry making projects, as well. We've also shown a couple of 5.5mm split rings in the picture to give you an idea of the loop size in the chain. The chain is 3.3mm wide, measured on the larger links; the large links are about 5mm long. The smaller "figure 8" shaped links are about 1.8mm wide. All the links are closed (soldered). The chain is formed from heavier gauge stock (about 25ga) than many of the lightweight GF chains that you commonly find available in the bead market. 14kt GF. Sold by the foot.