Starrett 50989 Micrometer Calibration Standard 11 in

Product Description

The STARRETT 50989 is a spherical end micrometer calibration standard designed to verify and maintain the accuracy of outside micrometers used in precision measurement work. At 11 inches in length and calibrated to an accuracy of 0.000170 inches, this standard provides a reliable reference for technicians performing gauge calibration in shop, lab, or field environments. The included heat insulating handle minimizes dimensional error caused by thermal expansion from hand contact during use. Calibration standards like this one are essential tools for metrology technicians, quality control personnel, and precision tradespeople who require traceable measurement verification.

This calibration standard is suited for use with outside micrometers requiring an 11-inch reference length. It is appropriate for industrial, manufacturing, and inspection environments where measurement accuracy must be routinely verified and documented. The spherical contact ends ensure consistent, repeatable contact geometry when setting or checking micrometer anvil alignment. It is typically used in machine shops, tool rooms, calibration labs, and quality assurance departments.

Key Features

• Calibrated to 0.000170 inch accuracy for precise micrometer verification
• 11-inch length accommodates large-range outside micrometers
• Spherical end geometry ensures consistent contact and repeatable readings
• Includes heat insulating handle to prevent thermal growth during handling
• Factory calibrated — ready for use as a reference standard out of the box

Compatibility

Designed for use with outside micrometers requiring an 11-inch calibration reference. Suitable for standard outside micrometer designs that accept spherical end calibration standards of this length.

Installation Notes

Calibration standards should be handled using the provided heat insulating handle to prevent body heat from affecting dimensional accuracy. Store the standard in its protective case when not in use and allow it to reach ambient temperature before use in controlled calibration environments. Calibration procedures should follow applicable metrology standards and be performed by qualified personnel with appropriate documentation practices.