Vermont Gage 112318390 Class Zz Plus Plug Gage 18.39mm

Product Description

The VERMONT GAGE 112318390 is a Class ZZ Plus plug gage machined from tool steel for dimensional inspection of bored holes and machined features. It checks whether a hole meets its minimum acceptable size, making it a go gage by function. At 18.39 mm in diameter with a tolerance of 0.005 mm, this gage delivers the precision required for close-tolerance work. Overall length is 2.0000 inches, keeping the gage easy to handle during bench inspection. Each unit ships with a Certificate of Accuracy traceable to NIST, confirming the measurement is backed by a documented calibration chain. Machinists, quality technicians, and toolroom personnel are the primary users.

This plug gage is suited for go inspection tasks in production environments, metrology labs, and toolrooms. It is sized for components requiring an 18.39 mm hole diameter and is compatible with standard gage handle systems. The gage is also used to verify and set micrometers, verniers, and other measuring devices to a known standard. Both light manufacturing and high-precision machining operations rely on Class ZZ Plus gages when parts must conform to ASME B89.1 dimensional standards. The 10 Micro coating finish helps protect the gage surface during repeated insertions.

Key Features

• 18.39 mm diameter with 0.005 mm tolerance for close-tolerance go inspection
• Tool steel construction for wear resistance and dimensional stability
• 10 Micro surface coating finish protects the gage land during service
• Overall length of 2.0000 inches fits standard gage handles
• Includes Certificate of Accuracy with NIST traceability
• Conforms to ASME B89.1 standards

Compatibility

Designed for use in go inspection of 18.39 mm diameter bored holes and machined features. Also used to set and verify micrometers, verniers, and other measuring devices. Fits standard plug gage handle assemblies sized for this diameter range.

Installation Notes

Plug gages are handled and used by quality technicians and machinists; no special installation tools are required, but clean, dry hands or lint-free gloves are recommended to prevent corrosion. Before use, ensure the gage and the part being inspected are at the same temperature to avoid thermal expansion errors. Apply a light film of instrument oil to the gage land to reduce wear during repeated insertions. Store the gage in its case or on a padded surface away from other metal tools to protect the calibrated surface.