Spi CMS160725111 Dial Drop Indicator 0.25 in Range

Product Description

The SPI CMS160725111 is a dial drop indicator designed for precision dimensional measurement in machining, metrology, and quality-control applications. It provides a 0.25 inch total measurement range with a 0-25-0 bidirectional dial reading and a fine graduation of 0.0005 inches per division, giving technicians the resolution needed to detect minute surface variations, runout, or part deviation. The 2.2 inch white dial face promotes easy reading under shop conditions. Accuracy is rated at 0.0015 inches, and the indicator ships with a NIST traceability certification confirming it meets US Federal Specifications and AGD Group 2 standards. Machinists, quality inspectors, and tool-and-die technicians are the primary installers and users of this instrument.

This indicator is suited for use on surface plates, magnetic bases, and indicator holders in both production and inspection environments. Typical applications include checking shaft runout, verifying flatness, indicating parts into a chuck or vise, and inspecting machined surfaces against print tolerances. The 3/8 inch stem diameter fits standard AGD-compatible holders and arms. The flat back allows flush mounting against indicator stands. The built-in revolution counter simplifies tracking of multi-revolution measurements within the 0.25 inch range, reducing read errors during repetitive inspection cycles.

Key Features

• 0.25 inch total range with 0.0005 inch graduation for high-resolution measurement
• 0-25-0 bidirectional dial reading supports both positive and negative deviation checks
• Revolution counter tracks travel across the full 0.25 inch range at 0.05 inches per revolution
• 2.2 inch white dial face with counter pointer for easy, unambiguous reading
• 3/8 inch stem diameter with flat back for universal positioning and standard holder compatibility
• Includes NIST traceability certification meeting US Federal Specifications and AGD Group 2 requirements
• 1.50 N measuring force minimizes deflection on delicate or finished surfaces

Compatibility

Designed for use with standard AGD Group 2 indicator holders, magnetic bases, and universal positioning arms accepting a 3/8 inch stem diameter. Thread size is 4-48 and M2.5 for contact point interchange.

Installation Notes

Dial drop indicators are installed and used by machinists, metrologists, and quality technicians — no power source is required. Secure the 3/8 inch stem firmly in the holder or arm clamp before zeroing the dial to avoid measurement drift. Handle the indicator spindle with care and avoid dropping the unit, as internal gear mechanisms are precision-ground and sensitive to impact. Zero the dial at the reference surface before taking comparative measurements, and confirm the contact point thread size matches replacement stylus contacts before swapping tips.