The Mitutoyo Holtest mechanical three-point internal micrometer utilizes three self-centering anvils with precision contact points for accurate and efficient measurements of inside dimensions of bores (Holtest models under 5-6mm/0.24-0.28in - Two-Point Carbide Contact Points).

The Mitutoyo mechanical Holtest internal micrometer features three hardened-steel anvils evenly spaced at 120° for true alignment of the axis bore for accurate, easily repeatable measurements. Contact points are coated with Titanium Nitride (TiN) for added durability and precision (Holtest models under 5-6mm/0.24-0.28in - Two-Point Carbide Contact Points). The Holtest ratchet stop mechanism provides a constant measuring force on the hardened-steel spindle to ensure accurate, even measurements.

• Titanium-coated measuring pins provide excellent durability and impact resistance and allow the instrument to measure right to the bottom of a blind hole
• Three-point design ensures self-centering action for stable measurements in the range above 8mm bore diameter
• Bore micrometers fitted with the constant-force ratchet enable consistent measurements with minimal operator variation

• Available in Metric and Inch models (see chart)
• Extension rods for measuring deep holes are included with certain models (see chart)
• Setting rings for zero point adjustment with certain models (see chart)
• Scale on thimble and sleeve is laser etched for easier reading in all conditions
• Holtest up to 100mm / 4in diameter measurements - supplied in a fitted plastic case
• Holtest over 100mm / 4in diameter measurements - supplied in a fitted wooden case