Spi 29-498-3 Class Zz Plus Plug Gage 0.498 in Dia

Product Description

The SPI 29-498-3 is a Class ZZ Plus plug gage used to verify the dimensional accuracy of machined bores and holes. It is a go/no-go style precision measurement tool manufactured from steel, designed for use in quality control, inspection, and machining environments. The gage measures bores at a nominal diameter of 0.498 inches with a tolerance of 0.0002 inches, providing reliable dimensional verification at the bench or on the shop floor. Machinists, toolmakers, and quality inspectors use plug gages like this one to confirm that finished holes meet drawing specifications before parts move to assembly.

This plug gage is suited for general inspection tasks in manufacturing, job shop, and production environments where tight-tolerance bore verification is required. The 0.498-inch diameter targets bores in that specific nominal range, making it appropriate for applications where holes are drilled, reamed, or bored to near half-inch specification. It is a compact, single-piece tool that stores easily in a gage block set or tool crib and requires no power or calibration equipment to use in the field.

Key Features

• Class ZZ Plus accuracy with a 0.0002-inch tolerance for reliable bore inspection
• 0.498-inch nominal measurement diameter for near half-inch bore applications
• Steel construction for durability and wear resistance in production use
• Compact, lightweight design at 0.2 pounds for easy bench or floor use
• Single-piece tool requiring no power source or additional equipment

Compatibility

Designed as an OEM-style precision inspection tool for use wherever Class ZZ plug gages are specified for 0.498-inch nominal bore verification in machining and quality control applications.

Installation Notes

Plug gages are handled and used by machinists, toolmakers, and quality inspectors following standard metrology practices. Clean and degrease the bore and the gage before use to ensure accurate readings and prevent wear. Store the gage in a protective case away from other metal tools to avoid nicking the precision ground surface. Periodic recalibration against a traceable standard is recommended to maintain measurement integrity over time.