Starrett 71989 Micrometer Rod 7 to 8 Inches

Product Description

The STARRETT 71989 is a replacement micrometer rod designed for use with 443 and 445 Series micrometer depth gages. The rod extends the measurement range of compatible depth gages from 7 to 8 inches, allowing technicians and machinists to reach deeper bores, slots, and stepped surfaces without changing instruments. With a rod diameter of 5/32 inch (3.20 mm), it fits the standard spindle interface of the supported gage series. This accessory is installed by metrologists, tool room technicians, machinists, and quality control professionals working in precision measurement applications.

This rod is used in machine shops, tool rooms, and quality inspection environments where micrometer depth gages must measure features beyond the range of the base rod set. It is suited for both production floor use and bench inspection work. The 443 and 445 Series micrometer depth gages are the specified compatible instruments for this rod. Typical applications include measuring the depth of counterbores, keyways, recesses, and similar machined features that fall within the 7 to 8 inch range.

Key Features

• Extends micrometer depth gage measurement range to 8.0000 inches maximum
• Rod diameter of 5/32 inch (3.20 mm) matches the OEM interface specification
• Direct OEM accessory for 443 and 445 Series micrometer depth gages
• Sold individually as a single replacement rod
• Lightweight at 0.05 pounds for easy handling during bench work

Compatibility

Designed for use with STARRETT 443 and 445 Series micrometer depth gages as a direct accessory rod.

Installation Notes

Installation of this rod is performed by qualified metrology or tool room personnel familiar with micrometer depth gage assembly. Before swapping rods, ensure the gage is zeroed and the spindle area is clean and free of debris or burrs. Handle the rod carefully to avoid nicking the contact surface, as surface damage will affect measurement accuracy. Verify proper rod seating and re-zero the instrument before taking measurements.