Spi 29-450-4 Class Zz Plus Plug Gage 0.45 Inch

Product Description

The SPI 29-450-4 is a Class ZZ Plus plug gage designed to inspect and verify hole diameters to a nominal size of 0.45 inches with a tolerance of 0.0002 inches. Plug gages are precision hand tools used in dimensional inspection workflows to confirm that a bored, drilled, or reamed hole meets specified size requirements. The 29-450-4 is constructed from steel, providing the hardness and wear resistance needed for consistent, repeatable measurements in production and shop environments. Machinists, tool-and-die makers, and quality control technicians use Class ZZ Plus gages for general-purpose inspection where tight dimensional verification is required.

This plug gage is suited for use in machine shops, manufacturing facilities, and quality inspection departments where hole diameter verification is part of routine process control. Class ZZ Plus gages are commonly applied to incoming inspection, in-process checks, and final part verification on drilled or bored components. The 0.45-inch nominal diameter makes it appropriate for applications involving fastener clearance holes, bearing bores, and similar features requiring controlled dimensional tolerances.

Key Features

• Nominal diameter of 0.45 inches for precise hole size verification
• Tolerance of 0.0002 inches meets Class ZZ Plus accuracy standards
• Steel construction for durability and wear resistance in production use
• Compact and lightweight at 0.2 pounds for easy single-hand operation
• Single-piece package quantity suitable for individual tooling needs

Compatibility

Designed as a general-purpose Class ZZ Plus plug gage for verifying 0.45-inch nominal diameter holes in standard machined components and assemblies.

Installation Notes

Plug gages are used by machinists and quality technicians and require no permanent installation. Handle the gage with clean, dry hands or cotton gloves to prevent corrosion from skin oils. Store in a protective case away from other tooling to avoid contact damage to the precision-ground surfaces. Calibrate and inspect the gage periodically per your facility's metrology program to ensure continued accuracy.