Spi 19-056-1 Class Zz Minus Plug Pin Gage 0.056 in

Product Description

The SPI 19-056-1 is a Class ZZ minus plug pin gage with a 0.056-inch diameter, designed for go/no-go inspection of small bored holes and precision-machined features. Built from steel, this pin gage holds a tolerance of 0.0002 inches, consistent with Class ZZ minus specifications used in production inspection and quality control environments. Machinists, toolroom technicians, and quality inspectors use plug pin gages like this one to verify that a hole or bore falls within an acceptable dimensional range before parts move forward in the manufacturing process.

This gage is suited for inspection tasks in machine shops, manufacturing facilities, and tool rooms where close-tolerance bore verification is required. The 0.056-inch diameter targets small-diameter features common in precision components, instrument housings, and hydraulic or pneumatic valve bodies. It is typically used as part of a complete pin gage set or as a standalone replacement for a worn or out-of-tolerance gage in an existing set.

Key Features

• Class ZZ minus tolerance classification for production-grade hole inspection
• 0.056-inch nominal diameter for small-bore verification
• Steel construction for durability and dimensional stability
• 0.0002-inch tolerance for reliable go/no-go measurement
• Single-piece package quantity suitable for individual replacement use

Compatibility

Designed as an OEM-style replacement or standalone Class ZZ minus plug pin gage for use in standard pin gage handles and holders accepting 0.056-inch diameter pins.

Installation Notes

Pin gages should be handled with clean, dry hands or cotton gloves to prevent corrosion from skin oils. Before use, inspect the gage for burrs or surface damage that could affect measurement accuracy. Store pin gages in a protective case away from abrasive materials and temperature extremes to maintain dimensional integrity. Calibration checks against a traceable standard are recommended at regular intervals per your facility quality plan.