Spi CMS160725076 Disc Micrometer 3-4 in Ratchet Nist

Product Description

The SPI CMS160725076 is a mechanical disc micrometer designed for precision outside measurement in the 3 to 4 inch range. It uses a ratchet stop thimble to apply consistent measuring pressure, which reduces operator-to-operator variation during repeated measurements. Resolution is 0.0001 inches with an accuracy rating of 0.0002 inches. The disc-style anvil measures 0.79 inches in diameter, making it well suited for thin-walled parts, grooves, and recessed features that a standard flat anvil cannot reach cleanly. Steel anvil and spindle construction provide durability in shop environments. A Short Form Certificate of Calibration with NIST traceability is included, supporting quality and inspection requirements.

This micrometer is used in precision machining, tooling, quality control, and inspection applications where a standard outside micrometer cannot access the measurement surface. The disc anvil configuration is particularly useful when measuring across grooves, slots, thin flanges, or near shoulders. It is suited for use on the shop floor, in metrology labs, and in manufacturing environments where documented calibration is required. The included case protects the instrument during storage and transport between workstations or job sites.

Key Features

• Measurement range of 3 to 4 inches for larger precision components
• Resolution of 0.0001 inches for fine measurement discrimination
• Accuracy rated at 0.0002 inches
• 0.79-inch diameter disc anvil for access to grooves and recessed surfaces
• Ratchet stop thimble delivers repeatable, consistent spindle pressure
• Steel anvil and spindle material for wear resistance in production environments
• NIST traceability certification and Short Form Certificate of Calibration included

Compatibility

Designed as an OEM-style precision measuring instrument for general outside measurement applications in the 3 to 4 inch range using a disc anvil configuration.

Installation Notes

This instrument requires no installation. Calibration verification against a known standard is recommended before first use and at regular intervals per your quality management program. Store in the included case when not in use to protect the measuring faces and thimble mechanism. Do not expose to coolant, oils, or abrasives beyond the instrument's rated water resistance, which is rated as none.