micrometer caliper 
Instrument that measures the thickness or the diameter of relatively small parts; it produces finer results than a vernier caliper.
Part that stops the finely threaded screw when the pressure on the object being measured is sufficient.
Horseshoe-shaped part that supports the anvil and a graduated device from which the measurement is read.
Cylindrical part that is attached to the frame of the micrometer to support the object to be measured; the object is placed between the anvil and the spindle.
Graduated cylindrical part that is activated by the finely threaded screw and measures the thickness with precision.
Cylindrical end of the finely threaded screw.
Ring-shaped part that locks the finely threaded screw in its final position to preserve the measurement obtained.
finely threaded screw
Screw driven by the ratchet knob that moves the spindle against the object to be measured.