Spi 29-858-8 Class Zz Plus Plug Gage 0.858 in

Product Description

The SPI 29-858-8 is a Class ZZ Plus plug gage designed for go/no-go dimensional verification of hole diameters in precision machining and quality control environments. It measures a nominal diameter of 0.858 inches with a tolerance of 0.0002 inches, making it suitable for close-tolerance inspection work. Constructed from steel, this gage provides the durability and wear resistance expected in production and inspection settings. Machinists, quality technicians, and tool-and-die professionals use plug gages like this to confirm that bored, drilled, or reamed holes fall within specified acceptance limits.

This plug gage is used in shop-floor and inspection-room applications wherever a 0.858-inch bore or hole diameter must be verified against a tolerance band. Class ZZ Plus gages are typically applied in general-purpose inspection rather than high-precision master gage work, making them a practical choice for incoming inspection, in-process checks, and finished-part verification in both job shop and production environments.

Key Features

• Nominal measurement diameter of 0.858 inches for direct go/no-go hole inspection
• Class ZZ Plus tolerance of 0.0002 inches for reliable general-purpose dimensional verification
• Steel construction for wear resistance and dimensional stability in production environments
• Individual unit packaging suitable for bench, floor, or field inspection use

Compatibility

Designed as a general-purpose plug gage for verifying 0.858-inch nominal diameter holes in machined components across a wide range of materials and industries.

Installation Notes

Plug gages are handled and used by quality technicians or machinists and require no installation. Clean the gage and the bore being inspected before use to prevent debris from affecting measurement accuracy. Store the gage in its protective case away from extreme temperature changes to preserve dimensional stability. Do not force the gage into an undersized bore, as this can damage the gage surface and invalidate measurements.