Mitutoyo 468-977 Digimatic Holtest LCD Inside Micrometer, Interchangeable Head Set, 0.5-0.8"/12.7-20.32mm Range, 0.00005" Graduation, +/-0.0001" Accuracy (2 Piece Set)

The Mitutoyo 468-977 Holtest three-point internal micrometer has a measurement range of 0.5 to 0.8” and 12.7 to 20.32 mm, is titanium nitride (TiN)-coated, precise to 0.00005” or 0.001 mm, and accurate to + or - 0.0001”. TiN-coated measuring contact points offer increased durability and impact resistance over uncoated points, and contact point geometry allows the instrument to measure to the bottom of a blind hole. The ratchet stop offers constant force for repeatability. The micrometer has functions for presetting, zero/ABS (Absolute), auto power on/off, data hold, data output, error alarm, and a battery replacement alarm. Estimated battery life is eight months, under normal use. This gage set includes two interchangeable measuring heads, setting ring, extension rod, and fitted wooden case. Includes inspection certificate ensuring that the exact micrometer purchased has met National Institute of Standards and Technology master standards.

Bore gages measure holes, or bores, in a workpiece. They can measure the interior diameter of a hole at any depth, while internal micrometers can only measure to the depth of their teeth. Bore gages are typically calibrated with a setting ring. Bore gages come in two types, one simple, and the other direct-measuring. Simple bore gages are used with a caliper to transfer the hole measurement, while the more complex gages take the measurement directly, and display the measurement through a vernier, dial, or digital display. Bore gages have a two- or three-point contact, which indicates how many points on the gage head touch the inside of the bore. Two-point contacts are better at measuring ovality, while three-point systems are used to measure lobing, or triangular form error. Pistol-grip bore gages are used for fast, single-handed operation with good repeatability from one operator to another. Bore gages, regardless of type, can be used in some special applications, such as measuring threads, spline pitch diameters, and deep bores.

Mitutoyo manufactures precision measuring tools, metrology equipment, and systems. The company was founded in Tokyo in 1934 and formed Mitutoyo America Corporation in 1963, which is headquartered in Aurora, IL.

What’s in the Box?

• Mitutoyo 468-977 three-point internal micrometer
• 0.5 to 0.65” head
• 0.65 to 0.8” head
• 0.65” diameter setting ring
• Extension rod
• Two SR44 batteries
• Inspection certificate
• Fitted wooden case