English: Illustration of a micrometer caliper. The micrometer is showing a measurement of 7.145 mm ± 0.005 mm.

Legend:

1. Anvil: part that the spindle moves toward, and that the sample rests against
2. Spindle: moved by the thimble towards the anvil
3. Ratchet stop: limits applied pressure by slipping at a calibrated torque
4. Sleeve: stationary linear scale with 0.5 mm resolution
5. Frame: holds the anvil and barrel in constant relation to each other
6. Thimble scale: rotating linear scale with 0.01 mm resolution
7. Lock nut: used to block/release movable part
8. Thimble: moves the spindle while rotating the scale