Starrett 50988 Micrometer Calibration Standard 250mm

Product Description

The STARRETT 50988 is a spherical end micrometer calibration standard designed to verify and maintain the accuracy of outside micrometers. At 250mm in length, this reference bar provides a stable, precise setting reference for technicians performing routine calibration checks or zero-setting adjustments on outside micrometers. The included heat insulating handle minimizes dimensional error caused by thermal expansion from hand contact, which is critical when working to tight tolerances. This tool is used by quality control technicians, machinists, and metrology professionals who require traceable, repeatable calibration references in production and inspection environments.

This calibration standard is suited for use in machine shops, tool rooms, and inspection labs where outside micrometers require periodic verification. The 250mm length makes it appropriate for setting and checking large-range micrometers. It is a hands-on reference standard intended for bench use during tool calibration routines and is not a measuring instrument itself. Trade professionals in precision machining, aerospace, and general manufacturing will find this standard fits standard metrology workflows.

Key Features

• 250mm reference length for calibrating large-range outside micrometers
• Spherical ends provide consistent, repeatable contact points for accurate setting
• Includes heat insulating handle to prevent thermal expansion errors during handling
• Compact package weight of 0.5 pounds for easy bench handling and storage

Compatibility

Designed for use with outside micrometers requiring a 250mm calibration reference standard. No specific compatible model numbers were provided in the product data.

Installation Notes

This calibration standard requires no installation. Always use the included heat insulating handle when holding the standard to prevent body heat from affecting the reference dimension. Store the standard in its protective case when not in use to prevent surface damage to the contact ends. Calibration procedures should follow applicable metrology standards and shop quality control protocols.