Spi 29-749-9 Class Zz Plus Plug Gage 0.749 in

Product Description

The SPI 29-749-9 is a Class ZZ Plus plug gage machined to a nominal diameter of 0.749 inches with a tolerance of 0.0002 inches. Plug gages of this class are used to verify whether a machined hole or bore falls within an acceptable dimensional range. The Class ZZ designation indicates a commercial-grade tolerance tier suited for production inspection and quality control work. Constructed from steel, this gage provides the hardness and wear resistance required for repeated use in shop-floor measurement tasks. It is used by machinists, toolmakers, quality technicians, and precision metrology personnel.

This plug gage is suited for inspecting drilled, reamed, or bored holes in metal and machined components where a 0.749-inch nominal diameter tolerance check is required. It is appropriate for both job shop and production environments where go/no-go verification is part of the inspection process. Class ZZ gages are commonly applied in situations where moderate gage tolerance is acceptable, making this a practical choice for general production inspection rather than master or reference gage applications.

Key Features

• Nominal measurement diameter of 0.749 inches for direct hole inspection
• Class ZZ Plus tolerance of 0.0002 inches for commercial-grade production inspection
• Steel construction for hardness and durability under repeated use
• Compact and lightweight at 0.2 pounds for easy handling at the workstation
• Single-piece package quantity — no minimum stocking commitment beyond one unit

Compatibility

Designed as a standard commercial plug gage for inspecting machined bores and holes with a nominal diameter of 0.749 inches. Compatible with any inspection process or fixture that accepts a Class ZZ plug gage at this nominal diameter.

Installation Notes

Plug gages are handled and used by quality technicians and machinists — no installation in the traditional sense applies. Before use, clean the gage and the hole to be checked to remove chips, coolant, and debris that could affect the measurement. Do not force a plug gage into an undersized hole, as this can damage both the gage and the workpiece. Store the gage in a protective case away from other tooling to prevent contact damage to the precision-ground surface.