Spi 29-153-4 Class Zz Plus Plug Gage 0.153 in Dia

Product Description

The SPI 29-153-4 is a Class ZZ Plus plug gage designed for precision hole and bore inspection in machine shop and quality-control environments. It measures bore diameters at 0.153 inches with a tolerance of 0.0002 inches, making it suitable for go/no-go verification of tight-tolerance drilled, reamed, or bored features. Constructed from steel, it is built to withstand repeated use in production inspection routines. Machinists, toolmakers, and quality technicians use this type of gage to confirm that a hole falls within the specified tolerance range before a part advances to the next stage of production.

This plug gage is used in precision manufacturing and inspection applications where bore diameter conformance must be verified quickly and reliably. Typical environments include job shops, production floors, and quality labs working with metal, plastic, or composite parts that require close-tolerance hole control. The compact form factor and steel construction make it practical for bench inspection as well as in-process checks at the machine.

Key Features

• Class ZZ Plus tolerance classification for reliable go/no-go bore inspection
• 0.153-inch measurement diameter for small-bore applications
• 0.0002-inch tolerance for high-precision dimensional verification
• Steel construction for durability and dimensional stability
• Compact single-piece design suited for bench and in-process use

Compatibility

Designed as an OEM-style replacement or direct-use plug gage for any application requiring Class ZZ Plus go/no-go inspection of 0.153-inch nominal bore diameters.

Installation Notes

Plug gages are handled and used by machinists and quality technicians rather than installed in a traditional sense. Store the gage in a protective case when not in use to prevent wear on the gage surfaces. Clean and degrease the bore and gage surfaces before inspection to avoid false readings. Follow your facility's gage calibration and handling procedures to maintain measurement integrity.