Spi 19-490-2 Class Zz Minus Plug Pin Gage 0.49 Inch

Product Description

The SPI 19-490-2 is a Class ZZ minus plug pin gage machined to a nominal diameter of 0.49 inches with a tolerance of 0.000200 inches. Plug pin gages are single-piece cylindrical tools used to verify whether a drilled, reamed, or bored hole falls within a specified dimensional tolerance. The minus designation means the gage is ground to the low end of the tolerance band, making it suitable for go/no-go inspection routines in quality control and machining environments. The body is constructed from steel, providing the hardness and wear resistance needed for repetitive gauging work. Machinists, tool-and-die makers, and quality technicians are the primary users.

This pin gage is suited for use in machine shops, manufacturing facilities, and inspection departments where precise hole verification is required. It is commonly used alongside a corresponding plus gage in go/no-go sets to confirm that a hole is within the acceptable size range. The 0.49-inch diameter addresses a common bore size encountered in general precision machining and fixture work. Its compact size makes it easy to handle during high-volume inspection tasks.

Key Features

• Class ZZ minus tolerance designation for low-end-of-band hole inspection
• Nominal diameter of 0.49 inches for a widely used bore size
• Tolerance of 0.000200 inches for precise dimensional verification
• Steel construction for durability and wear resistance in repetitive use
• Single-piece cylindrical form — no moving parts, no calibration required

Compatibility

Designed as an OEM-style replacement or direct-use plug pin gage compatible with standard pin gage handles and sets accepting 0.49-inch diameter pins in Class ZZ minus configurations.

Installation Notes

Pin gages are installed by hand into a standard gage handle or used as a standalone check pin — no tools required. Clean the hole and gage surface before use to avoid false readings from chips or debris. Store the gage in a protective case away from other metal tools to prevent surface damage. Handle with clean cotton gloves to minimize corrosion from skin oils.