Standard Pack = 1 piece(s). Starrett INYankee IN Calipers and Dividers are made from a high-grade steel and well-finishedThe bow spring, although flexible, is exceedingly strong to assure reliabilityAll Sizes are available with either spring nut or solid nutThe Starrett quick-adjusting automatic-closing spring nut is designed for making fast, positive adjustmentsFulcrum stud is Hardened and has a smooth bearing surfaceThe legs are made of flat stock and are very durableThe threads of the nut firmly engage the screw at the slightest press