Calipers--firm joint calipers use friction at the joint to hold the legs not move,measuring calipers
Firm joint inside caliper--made of stainless steel for superior hardness that reduce wear-outs and insure longevity,joint calipers
Measuring tool--excellent workmanship, smooth surface and edges without any burr,outside caliper
Inside calipers measuring tool--a useful measurement transfer tool when working with round stock or shaped materials and then transferring that measurement to a ruler,inside caliper
External caliper--wide application, can be applied for sculpture, pottery, tube and so on,measuring tool