Spi 19-187-4 Class Zz Minus Plug Pin Gage 0.187 in

Product Description

The SPI 19-187-4 is a Class ZZ minus plug pin gage ground to a nominal diameter of 0.187 inches with a minus tolerance of 0.000200 inches. It is used to verify that a drilled, reamed, or machined hole falls within a specified dimensional tolerance. The gage is machined from steel for wear resistance and dimensional stability. Class ZZ gages are the standard working-grade tool used in production inspection environments where go/no-go verification is required. Machinists, toolmakers, and quality technicians use this type of gage as part of routine dimensional inspection.

This pin gage is suited for inspection of small-diameter holes in metal, plastic, or composite workpieces across manufacturing, fabrication, and machine shop environments. The 0.187-inch diameter makes it appropriate for checking holes produced by standard fractional or wire-gauge drill sizes in that range. It is a single-pin gage and is commonly used as part of a larger pin gage set or as a standalone replacement for a worn or lost gage of this size.

Key Features

• Class ZZ minus tolerance ground to 0.000200 inches below nominal diameter
• Steel construction for durability and dimensional stability under repeated use
• 0.187-inch nominal diameter for inspection of small precision holes
• Single-pin format for use as a standalone gage or set replacement
• Minus designation confirms the gage will not overstuff a hole at the nominal dimension

Compatibility

Designed as an OEM-style working gage for use in standard pin gage handle sets accepting the 0.187-inch diameter pin size in the Class ZZ tolerance range.

Installation Notes

Pin gages should be handled with clean, dry hands or cotton gloves to prevent dimensional error from skin oils and temperature transfer. Before use, clean the gage and the hole being measured with a lint-free cloth. Do not force the gage into a hole; forcing can damage the gage surface and produce false readings. Store individually or in a padded gage roll to prevent contact wear against other tools.