Precision Spheres are used in a wide range of applications including the measurement of spline gears, small internal tapers, internal annular grooves and throated worm wheels. • Each standard set of Spheres contains a range of sizes with three matched spheres per size. • Manufactured from high Carbon Chrome Steel (AISI 52100-EN31). • Metric sizes range from 1 to 25mm or 1.5 to 12.5mm each in 1mm steps. • Inch sizes range from 1/16 to 1/2 inch in 1/32 inch steps or 9/16 to 1 inch in 1/16 inch steps. • Special combination sets and individual sizes available. • Different materials available.