Mitutoyo 2904A Dial Drop Indicator 1 in 0.001 Grad

Product Description

The MITUTOYO 2904A is a dial drop indicator designed for dimensional inspection and surface measurement in manufacturing, machining, and metrology applications. It delivers a 1-inch measuring range with a 0.001-inch graduation, giving technicians and machinists precise linear displacement readings in English units. The white-faced dial reads 100-0, and a built-in revolution counter tracks full-spindle rotations across the 1-inch range. The lug back mount allows secure fixture to magnetic bases, indicator holders, and transfer gages. This instrument meets ANSI/AGD standards and carries an AGD Group 2 designation, confirming it to a widely recognized dimensional and mechanical specification for dial indicators.

The 2904A suits toolroom inspection, machine setup, runout checking, and part comparison tasks on mills, lathes, surface plates, and CMM fixtures. It is a common choice for machinists, quality technicians, and tool and die professionals who require repeatable contact-measurement results. The 2-1/4-inch dial face provides clear readability in tight fixture setups. With a measuring force of 1.80 N, spindle deflection on delicate workpieces is minimized during contact measurement.

Key Features

• 1-inch total measuring range in English units
• 0.001-inch graduation for precise linear displacement readings
• Built-in revolution counter tracks full spindle rotations
• Lug back mount for compatibility with standard indicator holders and magnetic bases
• White dial face with 100-0 reading for easy visual interpretation
• Meets ANSI/AGD standards, AGD Group 2 designation
• Low 1.80 N measuring force reduces deflection on sensitive workpieces

Compatibility

Designed for use with standard AGD Group 2 indicator holders, magnetic bases, and transfer gage fixtures that accept a 0.375-inch stem diameter and lug back mounting.

Installation Notes

Installation and use of precision dial indicators is typically performed by machinists or quality technicians without special licensing requirements. Secure the lug back to the appropriate holder before contacting the workpiece, and verify the spindle moves freely through its full range prior to measurement. Do not overtighten the mounting clamp against the stem, as this can bind the spindle and introduce measurement error. Zero the dial face after securing the indicator at the desired contact point.