123 Series Rotating Disc Micrometers - Imperial

For measuring a displacement over a given number of gear teeth, closely spaced sections, ribs, keys and fins etc.
Measurable gear pitch: 0.5-6 module.
Graduation: 0.01mm (.001").
Parallelism 0-50mm 4µm, 50-100mm (4+L/50)µm, Flatness 1µm, Instrument Error 0-50mm ±4µm, 50-100mm ±6µm.
L = maximum measuring length.