Spi MS160712021 Micrometer Calibration Standard 21 in

Product Description

The SPI MS160712021 is a spherical end micrometer calibration standard designed for verifying and calibrating outside micrometers in precision measurement applications. Measuring 21 inches in length and calibrated to an accuracy of 0.0002 inch, this standard provides a reliable reference for ensuring instrument accuracy in demanding shop and metrology environments. It includes a heat insulating handle, which prevents thermal expansion errors caused by hand contact during measurement. Calibration standards of this type are used by machinists, quality control technicians, and metrology professionals who need traceable reference standards for routine gauge verification.

This calibration standard is suited for use in machine shops, manufacturing facilities, and quality labs where outside micrometer accuracy must be maintained. The spherical contact ends allow consistent, repeatable seating against micrometer anvils across the full 21-inch range. The included heat insulating handle supports accurate readings by minimizing heat transfer from the user to the standard during handling. It ships as a single unit and is appropriate for both shop-floor calibration checks and formal gauge R and R procedures.

Key Features

• 21-inch length covers large outside micrometer ranges
• Accuracy up to 0.0002 inch for precise calibration reference
• Spherical end geometry ensures repeatable anvil contact
• Calibrated at the factory for immediate use out of the box
• Heat insulating handle reduces thermal expansion error during use

Compatibility

Designed for use with outside micrometers as a calibration and verification reference standard. Compatible with micrometers requiring a 21-inch calibration standard.

Installation Notes

Calibration standards are handled by metrology technicians or qualified QC personnel, not installed in a traditional sense. Store the standard in its case when not in use to protect the contact surfaces. Always allow the standard to reach ambient temperature before use to avoid thermal measurement error. Handle by the insulating grip only to maintain measurement integrity.