Spi 19-590-9 Class Zz Minus Plug Pin Gage 0.59 in

Product Description

The SPI 19-590-9 is a Class ZZ minus plug pin gage used to verify hole diameters in machined parts and assemblies. It checks a nominal diameter of 0.59 inches with a minus tolerance of 0.0002 inches, confirming that a hole falls within the acceptable lower boundary of the specified dimension. Machinists, toolroom technicians, and quality control inspectors use plug gages like this one as part of go/no-go inspection workflows. The gage is manufactured from steel, providing the hardness and wear resistance required for repeated contact measurements in a production or inspection environment.

This gage is suited for inspecting drilled, reamed, or bored holes in metal, plastic, or composite workpieces where tight dimensional control is required. Class ZZ is the most common tolerance class for general-purpose inspection and is appropriate for shop-floor and toolroom use. It is typically used as a no-go member in a plug gage set, or as a standalone check when verifying that a hole has not been bored oversize. Applications include checking holes in fixtures, housings, brackets, and similar machined components across manufacturing and maintenance environments.

Key Features

• Class ZZ tolerance grade for general-purpose dimensional inspection
• Minus designation confirms the gage reflects the lower tolerance boundary of the nominal diameter
• 0.0002 inch tolerance for precise go/no-go verification
• Steel construction provides hardness and durability for repeated use
• 0.59 inch nominal diameter covers a common range of machined hole sizes

Compatibility

Designed as a standard Class ZZ minus plug pin gage for use in general-purpose hole inspection applications where a 0.59 inch nominal diameter is specified.

Installation Notes

Plug pin gages are handled and used by machinists and quality technicians following standard metrology practices. The gage should be cleaned and lightly oiled before and after each use to prevent corrosion and ensure accurate readings. Do not force the gage into a hole; insertion should be smooth and require no more than light hand pressure. Store the gage in its case or protective holder when not in use to prevent damage to the precision-ground surface.