Spi 29-865-3 Class Zz Plus Plug Gage 0.865 in

Product Description

The SPI 29-865-3 is a Class ZZ Plus plug gage designed to verify the dimensional accuracy of drilled, reamed, or bored holes with a nominal diameter of 0.865 inches. Built from steel, this go/no-go style gage delivers a tolerance of 0.0002 inches, meeting Class ZZ Plus standards for general-purpose inspection in production and maintenance environments. Machinists, quality technicians, and toolroom professionals use plug gages like this to confirm hole size conformance without relying on indirect measuring instruments. The 29-865-3 is a straightforward, reliable attribute gage suited for shop-floor verification work.

This plug gage is appropriate for use in metalworking, machining, and fabrication settings where hole diameter verification is a routine part of quality control. It is used to check holes produced by drilling, boring, or reaming operations in both light manufacturing and heavy industrial applications. The compact, lightweight form factor makes it easy to handle at the workpiece. A single-piece unit at this diameter class is common in job shops, production lines, and maintenance repair operations that require quick, repeatable go/no-go checks.

Key Features

• Class ZZ Plus tolerance rating of 0.0002 inches for reliable attribute inspection
• Nominal measurement diameter of 0.865 inches
• Steel construction for durability in shop-floor conditions
• Lightweight at 0.2 pounds for easy single-hand use
• Single-piece package quantity for individual toolroom or production use

Compatibility

Designed as a standard Class ZZ Plus plug gage for general-purpose hole inspection at 0.865 inches nominal diameter. Compatible with any application requiring attribute-style go/no-go verification at this diameter and tolerance class.

Installation Notes

Plug gages are used by machinists and quality control technicians and require no installation. Before use, clean both the gage and the hole being checked to remove chips, coolant, and debris that can affect readings. Do not force the gage through a hole; excessive force can damage the gage or the workpiece and will produce unreliable results. Store the gage in a protective case away from moisture and temperature extremes to maintain calibration integrity.