Spi 29-109-6 Class Zz Plus Plug Gage 0.109 in

Product Description

The SPI 29-109-6 is a Class ZZ Plus plug gage designed to verify the inside diameter of holes and bores with a nominal measurement of 0.109 inches. Class ZZ is a go/no-go tolerance grade suited for production inspection of general-purpose machined features. This gage carries a tolerance of 0.0002 inches, providing reliable pass/fail verification at the workpiece. Constructed from steel, it is built to withstand regular shop-floor use. Machinists, toolmakers, and quality control technicians use plug gages like this to confirm that drilled, reamed, or punched holes fall within specified limits before parts advance to the next stage of production.

This plug gage is suited for use in manufacturing, job shop, and toolroom environments where precise hole inspection is required. It is appropriate for incoming inspection, in-process quality checks, and final acceptance gauging of parts produced to standard tolerances. The 0.109-inch diameter targets small-diameter bore applications common in machined components, sheet metal work, and precision fabrication. Because Class ZZ is a production-grade tolerance class, this gage is best applied where moderate accuracy requirements apply rather than master or reference-grade inspection tasks.

Key Features

• 0.109-inch nominal diameter for small-bore inspection
• Class ZZ Plus tolerance grade rated at 0.0002 inches
• Steel construction for durability in production environments
• Compact form factor suited for hand use at the machine or inspection bench
• Go/no-go gauging method provides immediate pass/fail determination

Compatibility

Designed as an OEM-style replacement or direct-use plug gage for any application requiring inspection of a 0.109-inch nominal inside diameter to Class ZZ Plus standards.

Installation Notes

Plug gages are handled and used by machinists, toolmakers, and quality technicians rather than installed in the traditional sense. Before use, clean both the gage and the bore being inspected to remove chips, coolant, and debris that could affect the reading. Apply light gage oil when checking ferrous bores to prevent corrosion and reduce wear on the gage surface. Store the gage in its protective sleeve or case when not in use to preserve its calibrated tolerance and surface finish.