3-Point Micrometer

Three-point internal micrometers for bore diameter measurement with single-pass centering. Measures out-of-roundness and taper simultaneously.

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Technical Specifications

MITUTOYO 3-Point Micrometer

Full specification and available models for this brand. Pricing on enquiry.

MITUTOYO full specification

Series: Holtest 468 Digimatic / 368 Mechanical
Instrument Type: 3-Point (Three-Point) Self-Centering Internal Micrometer
Brand Name: Holtest (Mitutoyo)
Measuring Method: Three-point self-centering; three anvils spaced evenly at 120°
Contact Point Material: Titanium Nitride (TiN) coated (models ≥6 mm / 0.275"); Alloy steel (Series 368 Type II)
Graduation / Resolution (Series 368 Mechanical): 0.001 mm (6–12 mm range); 0.005 mm (12–300 mm range) / 0.0001" (≤0.5"); 0.0002" (>0.5")
Resolution (Series 468 Digimatic): 0.001 mm / 0.00005" (up to 8"/203.2 mm); 0.001 mm / 0.0001" (>8")
Accuracy / Instrumental Error (Series 368): ±3 µm (6–75 mm); ±4 µm (75–100 mm); ±5 µm (100–200 mm); ±6 µm (200–300 mm). Inch: ±0.00015" to ±0.00030"
Accuracy / Instrumental Error (Series 468): ±2 µm (6–12 mm); ±3 µm (12–50 mm); ±4 µm (50–100 mm); ±5 µm (100–200 mm); ±6 µm (200–300 mm)
Measuring Force: Controlled by ratchet stop mechanism (constant measuring force on hardened-steel spindle); specific Newton value not published in official catalogue
Repeatability: Ensured by ratchet stop; numerical value not published in official Mitutoyo catalogue
IP Rating (Series 468 Digimatic): IP65
IP Rating (Series 368 Mechanical): Not rated (no IP designation published)
Data Output (Series 468): SPC data output (Digimatic interface); Functions: Zero/ABS Setting, Data Hold, Data Output, Function Lock, 2 Presets, inch/mm conversion
Data Output (Series 368): None (mechanical)
Display (Series 468): LCD digital display
Battery (Series 468): SR44 × 2 (Model 938882); approx. 1.2 years battery life
Scale Type (Series 368): Laser-etched graduated thimble (analog)
Measuring Range Coverage: 6 mm to 300 mm (metric); 0.275" to 12" (inch/metric)
Extension Rod: Optional extension rods available (P/N 952621, 952622, 952623) for deep-hole measurement
Case / Supply: Fitted plastic case (models ≤100 mm / 4"); Wooden case (models >100 mm / 4")
Standards: Not explicitly listed in official catalogue pages reviewed

Full 6–300 mm coverage, inch/metric heads, and mechanical Series 368 (no IP, analog) available on request.

Available Models · 10

Series 468 Digimatic, 6–8 mm, Resolution 0.001 mm, Accuracy ±2 µm, IP65, SPC
Model: 468-161
Series 468 Digimatic, 10–12 mm, Resolution 0.001 mm, Accuracy ±2 µm, IP65, SPC
Model: 468-163
Series 468 Digimatic, 20–25 mm, Resolution 0.001 mm, Accuracy ±3 µm, IP65, SPC
Model: 468-166
Series 468 Digimatic, 30–40 mm, Resolution 0.001 mm, Accuracy ±3 µm, IP65, SPC
Model: 468-168
Series 468 Digimatic, 50–63 mm, Resolution 0.001 mm, Accuracy ±3 µm, IP65, SPC
Model: 468-170
Series 468 Digimatic, 75–88 mm, Resolution 0.001 mm, Accuracy ±4 µm, IP65, SPC
Model: 468-172
Series 468 Digimatic, 87–100 mm, Resolution 0.001 mm, Accuracy ±4 µm, IP65, SPC
Model: 468-173
Series 468 Digimatic, 125–150 mm, Resolution 0.001 mm, Accuracy ±5 µm, IP65, SPC
Model: 468-175
Series 468 Digimatic, 175–200 mm, Resolution 0.001 mm, Accuracy ±5 µm, IP65, SPC
Model: 468-177
Series 468 Digimatic, 200–225 mm, Resolution 0.001 mm, Accuracy ±6 µm, IP65, SPC
Model: 468-178

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Applications

Bore gauging on engine cylinders, hydraulic housings, and precision-bored CNC components.