A Micrometer is a device used for accurate measurement of components. A Micrometer has 2 opposing faces, an anvil and a spindle, that are joined by a frame. The anvil is stationary, while the spindle is a very accurately machined screw and the object to be measured is placed between the spindle and the anvil. The spindle is moved by turning the ratchet knob or thimble until the object to be measured is lightly touched by both the spindle and the anvil.

A Digital Point Micrometer includes both a pointed spindle and a pointed anvil for measuring the thickness of drills, small grooves, keyways, and other hard-to-reach dimensions.