Spi 19-771-5 Class Zz Minus Plug Pin Gage 0.771 in

Product Description

The SPI 19-771-5 is a Class ZZ minus plug pin gage designed for checking hole diameters in machined parts and assemblies. It measures 0.771 inches in diameter and is manufactured from steel for durability and dimensional stability under shop conditions. The minus tolerance designation means the gage is made to the low side of the nominal size, following standard GO gage convention. With a tolerance of 0.0002 inches, this gage provides reliable verification for quality control checks in production and maintenance environments. Machinists, toolmakers, and quality technicians use plug pin gages as a fast, repeatable method to confirm bore size without the need for indicating instruments.

This gage is suited for use in machine shops, manufacturing facilities, and maintenance shops where hole diameter verification is part of standard inspection procedures. It is appropriate for both production line go/no-go checks and general dimensional inspection work. The 0.771-inch nominal size covers a common bore diameter found in a range of mechanical components. It is a single-piece, hand-held tool that fits into standard gage holding fixtures and storage sets.

Key Features

• Class ZZ tolerance grade for standard workshop and production inspection
• Minus plug designation for GO-gage applications per standard gage convention
• 0.771-inch nominal diameter for direct hole size verification
• 0.0002-inch tolerance for consistent and repeatable dimensional checking
• Steel construction for wear resistance and long service life under shop conditions

Compatibility

Designed as a standard Class ZZ minus plug pin gage for use in general machining and inspection applications requiring verification of 0.771-inch nominal bore diameters.

Installation Notes

Plug pin gages are used by machinists and quality control technicians and require no installation. Before use, clean both the gage and the bore being checked to remove chips, oil, or debris that could affect accuracy. Handle gages with care to avoid dropping, as impact damage can alter the precision ground diameter. Store in a protective case away from other tools to prevent surface damage and maintain calibration integrity.