Spi 29-072-6 Class Zz Plus Plug Gage 0.072 Inch

Product Description

The SPI 29-072-6 is a Class ZZ Plus plug gage designed for precision hole and bore inspection in machine shops, manufacturing facilities, and quality control environments. Built to a tolerance of 0.0002 inches, this plug gage checks whether a drilled, reamed, or bored hole falls within a specified diameter of 0.072 inches. Constructed from steel, it delivers the dimensional stability required for repeatable go/no-go inspection work. Machinists, quality technicians, and toolroom professionals rely on this type of gage for high-frequency inspection tasks where manual measurement tools lack the required accuracy and speed.

This plug gage is suited for use in precision manufacturing settings where small-diameter holes must meet tight dimensional tolerances. It is appropriate for inspection of components produced on CNC mills, lathes, and drill presses where 0.072 inch bores are a standard feature. Class ZZ Plus gages are commonly applied in production inspection, first-article verification, and incoming quality control of machined parts. The compact form factor and single-ended design make it easy to use at the machine or at an inspection bench.

Key Features

• Class ZZ Plus tolerance grade for precision go/no-go hole inspection
• 0.072 inch nominal diameter for small-bore measurement applications
• 0.0002 inch tolerance for repeatable, accurate dimensional verification
• Steel construction provides durability and dimensional stability under repeated use
• Compact single-unit design suited for bench or point-of-machine inspection

Compatibility

Designed as an OEM-style replacement and standard inspection tool for use wherever a Class ZZ Plus plug gage of 0.072 inch diameter is specified in a quality control or manufacturing process.

Installation Notes

Plug gages require no installation but should be handled with clean, dry hands or cotton gloves to prevent corrosion from skin contact. Store the gage in a protective case away from chips, coolant, and abrasive debris when not in use. Allow the gage and workpiece to reach the same ambient temperature before inspection to avoid thermal expansion errors. Calibration should be verified periodically against certified reference standards in accordance with your facility quality system requirements.