Spi 19-427-4 Class Zz Minus Plug Pin Gage 0.427 in

Product Description

The SPI 19-427-4 is a Class ZZ minus plug pin gage machined to a nominal diameter of 0.427 inches with a minus tolerance of 0.0002 inches. Plug pin gages are precision inspection tools used to verify bore diameters, hole sizes, and internal feature dimensions to a known standard. The Class ZZ designation indicates a general-purpose tolerance grade suited for production floor inspection and go/no-go gauging applications. Constructed from steel, this gage provides the dimensional stability and wear resistance required for repeatable measurement in shop environments. It is handled by quality control technicians, machinists, and metrology personnel.

This gage is appropriate for use in manufacturing, machining, and quality assurance settings where hole diameter verification is required. At 0.427 inches nominal diameter, it covers a common bore size encountered in general metalworking and mechanical assembly inspection. The minus tolerance designation means the gage is ground undersized relative to nominal, making it suitable as a go-gage in standard gauging practice. It is a single-piece inspection tool requiring no calibration equipment on the shop floor beyond periodic cleaning and appropriate storage.

Key Features

• Nominal diameter of 0.427 inches for direct bore verification at that size
• Class ZZ minus tolerance of 0.0002 inches for general-purpose production gauging
• Steel construction provides durability and dimensional stability under shop conditions
• Single-piece plug gage design requires no assembly or adjustment before use
• Lightweight at 0.2 pounds for easy one-handed handling during inspection

Compatibility

Designed as a general-purpose Class ZZ plug pin gage for use with standard gage handle sets and holders sized to accept 0.427-inch diameter plug members. Verify handle compatibility with the gage shank diameter before use.

Installation Notes

Plug pin gages are inspection tools and do not require permanent installation. Before use, clean the gage and the bore being measured to remove chips, coolant, and debris that could cause false readings or damage the gage surface. Apply light gage oil when checking ferrous bores to reduce wear. Store the gage in a protective case away from other metal tools to prevent contact damage to the precision-ground surface.