Spi 29-407-4 Class Zz Plus Plug Gage 0.407 in Dia

Product Description

The SPI 29-407-4 is a Class ZZ Plus plug gage designed for dimensional verification of hole diameters at 0.407 inches. It provides a go/no-go reference point for machinists, quality control technicians, and toolroom personnel checking bore sizes on machined components. The gage holds a tolerance of 0.0002 inches, which meets Class ZZ Plus standards for inspection of production tooling and manufactured parts. The steel construction delivers the hardness and wear resistance required for repeated use in shop-floor and inspection environments.

This plug gage is used in machine shops, manufacturing facilities, and toolrooms where precise hole diameter verification is required. It is suited for incoming inspection, in-process quality checks, and final inspection of drilled, reamed, or bored holes at the 0.407-inch nominal diameter. Machinists and quality technicians install and use this gage by hand as part of standard dimensional inspection routines.

Key Features

• Class ZZ Plus tolerance rating for precision dimensional inspection
• Nominal measurement diameter of 0.407 inches
• Tolerance of 0.0002 inches for tight verification accuracy
• Steel construction for durability and wear resistance in production environments
• Compact and lightweight at 0.2 pounds for easy hand use

Compatibility

Designed as an OEM-style replacement or direct-use plug gage for inspection of 0.407-inch nominal bore diameters in standard Class ZZ Plus gage applications.

Installation Notes

Plug gages are handled and used by machinists or quality inspection personnel and do not require power tools or utility shutoffs. Store the gage in a protective case away from abrasive materials to prevent wear on the measuring surface. Clean the gage and the bore being checked before use to ensure accurate measurement. Follow your facility calibration schedule and applicable ASME B89 dimensional metrology standards for gage qualification and recertification intervals.