Spi 19-973-7 Class Zz Minus Plug Pin Gage 0.973 in

Product Description

The SPI 19-973-7 is a Class ZZ minus plug pin gage designed for precision bore and hole measurement in industrial and trade settings. With a nominal diameter of 0.973 inches and a tolerance of 0.0002 inches, this gage provides reliable go/no-go verification for machined holes, fixtures, and assemblies. Constructed from steel, it delivers the durability and dimensional stability required for repeated use in shop-floor and quality-control environments. Machinists, toolmakers, and quality inspection technicians rely on Class ZZ minus plug gages as a cost-effective standard for production-level inspection work.

This gage is suited for inspection of machined bores, drilled holes, and reamed features where tight dimensional control is required. Class ZZ is the standard tolerance class for plug gages used in general production inspection rather than master or reference applications. It is appropriate for use in manufacturing facilities, machine shops, fabrication shops, and maintenance environments where bore acceptance or rejection decisions must be made quickly and accurately.

Key Features

• 0.973-inch nominal diameter for precise hole inspection at that size
• Class ZZ tolerance grade — standard for production go/no-go inspection
• Minus designation ensures the gage falls within the minus tolerance range, protecting hole acceptance limits
• 0.0002-inch tolerance for repeatable, accurate measurement verification
• Steel construction for durability and dimensional stability under shop conditions

Compatibility

Designed as an OEM-style replacement or direct-use plug gage for any application requiring go/no-go inspection of a 0.973-inch nominal diameter bore using a Class ZZ minus tolerance standard.

Installation Notes

Plug pin gages are handled and used by machinists and quality inspection personnel — no power tools or trade licensing is required, but proper gage technique is essential for accurate results. Always clean the gage and the bore being inspected before use to prevent debris from affecting measurement. Store the gage in its protective case when not in use to prevent surface damage or corrosion that could affect dimensional accuracy. Do not force the gage into an undersized bore, as this can damage the gage surface and compromise its calibrated tolerance.