Spi 29-256-5 Class Zz Plus Plug Gage 0.256 Inch

Product Description

The SPI 29-256-5 is a Class ZZ Plus plug gage used to inspect and verify hole diameters in precision machining and quality control applications. It measures a nominal diameter of 0.256 inches with a tolerance of 0.0002 inches, making it suitable for go/no-go inspection work where tight dimensional control is required. Constructed from steel, this gage is designed to hold up under repeated use in shop environments. Machinists, quality technicians, and tool-and-die professionals use plug gages like this one as part of standard inspection routines on production and job-shop floors.

This plug gage is appropriate for verifying bored, drilled, or reamed holes in both production and prototype settings. It is a fit for light manufacturing, aerospace component inspection, and general metalworking shops where dimensional accuracy must be confirmed before parts advance to the next operation. The 0.256-inch diameter targets a specific hole size common in precision fastener and pin-fit applications. Class ZZ Plus tolerance class places this gage in the working-gage category, suited for routine inspection rather than master-gage calibration duties.

Key Features

• 0.256-inch nominal measurement diameter for targeted hole inspection
• Class ZZ Plus tolerance class at 0.0002 inches for reliable working-gage accuracy
• Steel construction for durability in production shop environments
• Compact and lightweight at 0.2 pounds for easy single-hand use
• Single-piece unit quantity for individual replacement or supplemental inventory

Compatibility

Designed as an OEM-style working gage for use with standard plug gage handles and frames sized for the 0.256-inch diameter range, consistent with common Class ZZ Plus gage system configurations.

Installation Notes

Plug gages should be handled with clean, dry hands or lint-free gloves to prevent corrosion from skin oils. Before use, verify the gage surface is free of burrs, nicks, or debris that could affect measurement accuracy. Store in a protective case away from temperature extremes to maintain dimensional stability. Calibration intervals should follow your facility quality management plan or applicable inspection standards.