Spi 34-203-0 Plug Thread Gage 2-56 2B Single End No Go

Product Description

The SPI 34-203-0 is a single-end, No Go plug thread gage used to verify internal thread compliance for 2-56 unified coarse threads classified to 2B tolerance. Manufactured from steel, this gage checks that a threaded hole does not accept an oversize or out-of-tolerance condition, ensuring only conforming parts pass quality inspection. It meets ANSI standards and includes NIST traceability certification, making it suitable for shop floor inspection, incoming quality control, and calibration lab use. A size 000 handle is required for operation and is sold separately.

This gage is used in precision manufacturing, aerospace, electronics, and instrumentation environments where small-diameter threaded fasteners must meet strict dimensional tolerances. The 2-56 thread size is common in miniature mechanical assemblies, instrument housings, and circuit board hardware. Quality technicians and machinists use No Go gages as the rejection criterion in a go/no-go inspection pair, confirming that internal threads are not oversized or stripped.

Key Features

• No Go classification rejects out-of-tolerance internal threads in 2-56 applications
• 2B thread class meets standard commercial and industrial fit requirements
• Steel construction for durability under repeated inspection use
• NIST traceability certification included for calibration documentation
• Meets ANSI standards for plug thread gage geometry and tolerance
• Single-end design sized for use with a size 000 handle (handle not included)

Compatibility

Designed for use with 2-56 unified internal threads classified to 2B tolerance. Requires a size 000 plug gage handle, sold separately. Intended for use as the No Go member of a standard go/no-go thread inspection pair.

Installation Notes

Plug thread gages are installed and used by quality control technicians and machinists — no power tools or electrical shutoff is required. Before use, ensure the gage and the workpiece threads are clean and free of chips or debris to prevent false readings or gage damage. Thread the gage by hand only; never force a plug gage into a threaded hole. Store gages in a protected case and handle with care to preserve calibration integrity.