This 3 layered 925 sterling silver necklace with rainbow moonstone is already perfectly spaced and on a single clasp with a 2 inch extension. The shortest chain is 14 inches, the second chain is a 4.5 herringbone chain that is 18 inches and the longest chain is 22 inches with moonstone and has a small crescent moon charm that dangles and extra 2 inches. This moonstone was hard to capture in a photo but includes a nice blue shimmer.