DIAL INDICATORS; DIAL TEST INDICATORS; ELECTRONIC DIGITAL INDICATORS; INSIDE DIAL INDICATORS; CENTERING INDICATORS; TWISTED-COIL COMPARATORS; VERNIER CALIPERS; DIAL CALIPERS; ELECTRONIC DIGITAL CALIPERS; MICROMETERS; GAUGE BLOCKS; PIN GAUGES; COMMON THREAD GAUGES; GEAR MEASURING APPARATUS IN THE NATURE OF GEAR ROLL TESTERS, GEAR MESH TESTERS, GEAR PITCHLINE RUNOUT TESTERS, GEAR TOOTH THICKNESS TESTERS AND GEAR PITCH VARIATION TESTERS WHICH CAN ACCOMPLISH A VARIETY OF GEAR MEASURING TASKS INCLUDING THE INSPECTION OF TOOTH DATA ON CYLINDRICAL GEARS AND HELICAL GEARS, SHAPING AND SHAVING CUTTERS, AS WELL AS ON WORM ROBS AND WORM WHEELS; WORM AND WORM GEAR MEASURING MACHINES WHICH CAN MEASURE ALL TOOTH DATA OF IN VOLUTE, LEAD LINE OF CONTACT AND INDIVIDUAL PITCH; GEAR MEASURING INSTRUMENT USED FOR CHECKING OF THE TOOTH PROFILE ERRORS, PITCH ERRORS AND LEAD ERRORS ON IN VOLUTE CYLINDRICAL GEARS AS WELL AS ON GEAR SHAVING AND SHAPING CUTTERS; IN VOLUTE AND LEAD MEASURING MACHINES; DOUBLE FLANK ROLLING GEAR TESTERS; AUTOMATIC PITCH MEASURING INSTRUMENTS; HOB LEAD MEASURING INSTRUMENTS; GEAR ECCENTRICITY TESTERS; FULLY AUTOMATIC CAMSHAFT MEASURING INSTRUMENTS FOR MEASUREMENT OF PRECISION INSTRUMENTS; OPTICAL COORDINATES MEASURING MACHINES USED TO MEASURE THE BASIC GEOMETRY ELEMENT, DISTANCE BETWEEN PLACES, VOLUMETRIC DISTANCE, ANGLE, POSITION ERROR, INTERSECTION AND SYMMETRY; OPTICAL DIVIDING HEAD WITH PROJECTION READOUT; BENCH-TOP PROJECTOR WHICH IS AN OPTICAL METROLOGIC INSTRUMENT BASED ON THE ENLARGED IMAGE, SHAPE AND FORM OF THE MACHINE PARTS AND IS SUITABLE FOR USE IN ENGINEERING INDUSTRY; DIGITAL HEIGHT GAUGES; AUTOMATIC TESTING MACHINES FOR DIAL INDICATOR; SURFACE ROUGHNESS COMPARISON TESTERS, WHICH ARE USED TO CALIBRATE THE SURFACE ROUGHNESS OF WORK PIECES BY COMPARISON ARE WIDELY USED IN MACHINERY INDUSTRY; SURFACE ROUGHNESS MEASURING INSTRUMENTS DESIGNED TO ASSESS THE SURFACE QUALITY OF THE WORKPIECE SUCH AS PLANE, TILT, CYLINDER, INNER HOLE AND DEEP GROOVE AS WELL AS BEARING RACEWAY ETC