Starrett 71979 Micrometer Rod 6 to 7 Inches

Product Description

The STARRETT 71979 is a replacement micrometer rod designed for use with 440 Series Micrometer Depth Gages. It extends the measurement range of the depth gage from 6 to 7 inches, allowing precise depth readings at the upper end of that interval. The rod measures 7.0000 inches in overall length and features a 1/8-inch diameter (3.20 mm), which is standard for this series. Metrology technicians, tool-and-die shops, machinist trades, and quality control personnel typically use this accessory when servicing or building out a depth gage set for larger measurement ranges.

This rod is suited for industrial and shop-floor applications where accurate depth measurement is required on bores, slots, shoulders, and stepped surfaces. It is a direct accessory component and is not a standalone measuring instrument. The 71979 fits into the existing 440 Series depth gage base without modification, making it a straightforward drop-in addition when a technician needs to extend measurement reach to the 6-to-7-inch range.

Key Features

• Extends 440 Series Micrometer Depth Gage range to the 6 to 7 inch interval
• Overall length of 7.0000 inches for precise fitment in the 440 Series base
• Rod diameter of 1/8 inch (3.20 mm) matches OEM specification
• Sold individually, allowing targeted range expansion without a full rod set
• Lightweight at 0.1 pounds, minimizing handling fatigue in repetitive use

Compatibility

Designed for use with STARRETT 440 Series Micrometer Depth Gages, as stated by the manufacturer. Verify the rod slot configuration of the specific 440 Series base before ordering.

Installation Notes

Installation of micrometer depth gage rods should be performed by a qualified machinist or metrology technician familiar with the 440 Series instrument. Before swapping rods, ensure the depth gage is clean and free of chips or coolant residue to avoid measurement error. Do not force the rod into the base; it should seat smoothly with finger pressure. After installation, verify calibration against a known reference standard before returning the instrument to service.