Spi 37-105-4 Plug Thread Gage M3x0.5 6H Single End Go

Product Description

The SPI 37-105-4 is a single-end Go plug thread gage designed to verify internal metric threads to the M3x0.5 thread form at 6H tolerance class. Used in quality control and inspection workflows, this gage confirms that a threaded hole meets the minimum material condition required for a mating fastener to pass through without interference. It is a precision inspection tool used by machinists, tool-and-die makers, and quality engineers on the shop floor or in the inspection lab. The gage is traceable to ANSI standards and calibrated against NIST reference standards, making it suitable for documented inspection processes.

This gage is applied wherever M3x0.5 internal threads are produced or inspected, including precision machined components, assembly fixtures, and manufactured parts requiring documented thread verification. It is a single-end Go gage only, used in tandem with a separate No-Go gage to complete a full accept-reject inspection cycle. The handle is not included and must be sourced separately to match the gage wire diameter of 0.12 inches.

Key Features

• Go plug configuration verifies minimum material condition of internal M3x0.5 threads
• 6H tolerance class suits standard commercial and precision metric threaded applications
• ANSI traceability certification included for documented quality control compliance
• Calibrated to NIST standards for use in regulated inspection environments
• Single-end design; handle not included — sold as gage member only
• Compact form factor: 1.16 inches in length, 0.12 inches in diameter

Compatibility

Designed for inspection of M3x0.5 internal threads at 6H tolerance class. For a complete Go/No-Go inspection setup, a matching No-Go gage member and a compatible handle sized for 0.12-inch wire diameter are required separately.

Installation Notes

Thread gages are precision inspection instruments and should be handled and stored with care to prevent damage to the gage member. Always clean the threaded hole being inspected before use to remove chips, coolant, or debris that could affect gage readings or cause premature gage wear. Do not force the Go gage — it should enter the full length of the thread under finger pressure only. Periodic recalibration against certified masters is recommended to maintain measurement integrity.