Spi 19-129-6 Class Zz Minus Plug Pin Gage 0.129 in

Product Description

The SPI 19-129-6 is a Class ZZ minus plug pin gage used to verify bore and hole diameters in precision machining and inspection applications. This gage measures 0.129 inches in diameter and is manufactured from steel for durability and dimensional stability. The minus tolerance designation means the gage is ground to the lower tolerance boundary, making it suitable for go/no-go gauging workflows where undersize verification is required. Machinists, quality control technicians, and tool room professionals use pin gages like this one to confirm that drilled, reamed, or bored holes fall within specification before parts move to the next stage of production.

This pin gage is suited for use in production inspection, incoming quality control, and toolroom environments. It works with standard pin gage handle sets and can be used as a standalone check gage or as part of a graduated pin gage set. Typical applications include verifying hole size in metal fabrication, aerospace components, automotive parts, and general precision machining. The 0.129 inch diameter covers a common drill size range used across a wide variety of manufactured parts.

Key Features

• Class ZZ tolerance grade — suitable for production and general inspection use
• Minus designation confirms the gage is ground to the lower tolerance limit for go/no-go applications
• 0.000200 inch tolerance for reliable dimensional verification
• Steel construction provides hardness and resistance to wear during repeated use
• 0.129 inch diameter covers a frequently used hole size in general machining

Compatibility

Designed as a standard replacement or supplement pin for Class ZZ minus pin gage sets and compatible with universal pin gage handles accepting 0.129 inch diameter pins.

Installation Notes

Pin gages should be handled with clean, dry hands or lint-free gloves to prevent corrosion from skin oils. Before use, verify that both the gage and the workpiece bore are clean and free of chips or debris. Store the gage in its protective case when not in use to prevent surface damage. Calibration and periodic inspection against a known standard is recommended to maintain measurement accuracy over time.