Spi 29-157-5 Class Zz Plus Plug Gage 0.157 in

Product Description

The SPI 29-157-5 is a Class ZZ Plus plug gage designed for precision hole measurement at a nominal diameter of 0.157 inches. Built from steel, this go/no-go style gage checks that a drilled, reamed, or bored hole falls within acceptable dimensional limits. It holds a tolerance of 0.0002 inches, making it suitable for quality control work where tight tolerances are required. Machinists, toolmakers, and QC inspectors use plug gages like this one as a fast, reliable method to verify hole size without requiring a measuring instrument readout.

This gage is intended for use on production floors, machine shops, and inspection stations where hole diameter verification is part of a standard quality process. At 0.157 inches, it fits applications involving small-diameter holes common in precision machined components. The Class ZZ Plus designation indicates a commercial-grade tolerance class appropriate for general inspection and in-process checking of manufactured parts.

Key Features

• Nominal measurement diameter of 0.157 inches for small-hole inspection
• Class ZZ Plus tolerance class suited for general-purpose quality control
• Tolerance of 0.0002 inches for consistent, repeatable measurement results
• Steel construction for durability in shop environments
• Compact, single-unit gage for fast pass/fail hole verification

Compatibility

Designed as an OEM-style replacement or direct-use plug gage for inspection of 0.157-inch nominal diameter holes in standard machining and quality control applications.

Installation Notes

Plug gages are used by machinists and quality control technicians and require no power or special tooling to operate. Handle the gage carefully to avoid dropping, which can alter its calibration or damage the precision ground surface. Store in a clean, dry location away from abrasive materials to maintain accuracy. Periodic recertification against a traceable standard is recommended to confirm the gage remains within stated tolerance.