Spi 29-277-1 Class Zz Plus Plug Gage 0.277 in

Product Description

The SPI 29-277-1 is a Class ZZ Plus plug gage designed to verify the dimensional accuracy of machined holes and bores to a nominal diameter of 0.277 inches. Built from steel, this go/no-go style gage delivers a stated tolerance of 0.0002 inches, making it appropriate for general-purpose inspection work in production and maintenance environments. Machinists, tool-and-die technicians, and quality-control personnel use plug gages like this one to confirm that drilled, reamed, or bored holes fall within acceptable dimensional limits before assembly or final inspection sign-off.

The 29-277-1 is suited for inspection of small-diameter holes in metal components across light manufacturing, job-shop machining, and maintenance repair operations. Class ZZ is the most commonly used tolerance grade for general-purpose inspection gages, making this an everyday working gage rather than a laboratory or master-grade instrument. It is well matched to applications where consistent, repeatable hole verification is needed on the shop floor or at the inspection bench.

Key Features

• Nominal measurement diameter of 0.277 inches for precise small-bore verification
• Class ZZ Plus tolerance rating at 0.0002 inches for reliable general-purpose inspection
• Steel construction for durability under regular shop-floor use
• Compact, lightweight design at 0.2 pounds for easy single-handed handling
• Single-piece packaging for individual replacement or toolbox stocking

Compatibility

Designed as an OEM-style replacement or direct stocking gage for general-purpose inspection applications requiring a Class ZZ plug gage at 0.277 inches nominal diameter.

Installation Notes

Plug gages are handheld precision instruments and do not require installation in the traditional sense. Handle with clean, dry hands or lint-free gloves to prevent corrosion from skin oils. Store in a protective case away from other metal tooling to avoid contact damage to the gage surface. Follow your facility's calibration schedule and handle in accordance with ASME B89 dimensional metrology standards for gage care and maintenance.