Spi 22-147-3 Class Zz Plug Gage Set 190 Piece

Product Description

The SPI 22-147-3 is a 190-piece Class ZZ plug gage set designed for precise hole measurement, slot width checks, and distance-between-hole calculations in industrial and trade inspection work. The set covers a diameter range of 0.061 to 0.25 inches with a minus tolerance of 0.0002 inches, meeting Class ZZ standards for go and no-go gaging inspection. All gages are manufactured from steel for durability and wear resistance. A Certificate of Accuracy with NIST Traceable documentation is included, supporting use in regulated quality environments. Machinists, tool-and-die technicians, and inspection department personnel are the primary users of this type of set.

This plug gage set is suited for production floor inspection, incoming parts verification, and toolroom applications where consistent, repeatable hole measurement is required. The 190-piece range provides broad coverage from small pilot holes through mid-range bores in the 0.061 to 0.25 inch span. The included pin gage holder keeps pins organized and accessible during use. Typical applications include measuring machined bores, verifying drilled and reamed hole sizes, checking slot widths on fabricated parts, and performing no-go inspection on threaded or plain holes to confirm conformance to print tolerances.

Key Features

• 190-piece set covering 0.061 to 0.25 inches in diameter
• Class ZZ minus tolerance of 0.0002 inches per pin
• NIST Traceable Certificate of Accuracy included with each set
• Steel construction for wear resistance and dimensional stability
• Pin gage holder included for organized storage and quick access
• Supports hole sizing, slot width measurement, and no-go gaging inspection

Compatibility

Designed as a general-purpose Class ZZ plug gage set compatible with standard pin gage holders and cases used in production inspection and toolroom environments where NIST Traceable documentation is required.

Installation Notes

Plug gages are handled and used by machinists, quality technicians, and inspection personnel rather than installed in a fixed sense. Before use, clean all pins and the workpiece bore with a lint-free cloth to remove oil, chips, or debris that could affect measurement accuracy. Never force a pin gage into a hole; apply light, consistent hand pressure only. Store pins in the provided holder away from direct contact with other metal tools to prevent nicks and dimensional damage that would invalidate the tolerance.