Starrett 83B-4 Spring Nut Dividers, Steel, Flat Leg, 0-8" Range

The Starrett 83B-4 “Yankee” spring-type divider calliper opens to 4” (100 mm) with sturdy construction and smooth action. It is made of flat stock, high-grade steel, for easily reproducible and accurate transfer of measurements, scribing lines, arcs and circles and marking distances between two points. This calliper has flat, straight legs and comes with a spring nut. Bow spring is flexible yet strong, for reliability. The centrally located adjustment rod ensures smooth action when opening and closing the calliper. The hardened fulcrum stud is strong to help prevent give or play in the measurement, which would reduce accuracy. Callipers measure the distance between two opposing sides of an object. They make inside, outside, depth or step measurements, according to their type. Callipers are commonly used in architecture, metalworking, mechanical engineering, machining, manufacturing, carpentry and medicine. The simplest callipers have two legs to mark the two points and require a ruler to take the measurement. More complex callipers use two sets of jaws instead of legs and have up to two graduated scales. Vernier, dial and digital callipers give direct and accurate readings and are functionally identical, having a calibrated scale with a fixed jaw and another jaw with a movable pointer that slides along the scale. The Vernier calliper has a scale sliding parallel to the main scale for an additional, fractional reading to improve measurement precision.