Spi 34-319-4 Plug Thread Gage 3/4-20 6H Single End Go

Product Description

The SPI 34-319-4 is a single-end Go plug thread gage designed to verify the minimum material condition of internal threads. Built to a 6H tolerance class for 3/4-20 thread forms, this gage checks that a threaded bore will accept a mating fastener at the low limit of the tolerance range. The gage body is machined from steel for dimensional stability and wear resistance. It is designed for use with a Size 3 handle, which is sold separately. Machinists, quality technicians, and manufacturing inspectors use Go plug gages as a standard go/no-go verification step during production and incoming inspection.

This gage is appropriate for inspecting 3/4-20 internally threaded components in precision manufacturing, aerospace, automotive, and general industrial applications. The single-end Go configuration is used when a matching No-Go gage is already on hand or when only minimum-limit verification is required. Traceability documentation to NIST standards is included with the gage, supporting quality management system requirements where documented calibration traceability is mandatory.

Key Features

• Go configuration checks that threaded bores meet minimum material condition for 3/4-20 thread
• 6H tolerance class per ANSI standards for precise thread verification
• Steel construction provides durability and dimensional stability under repeated use
• NIST traceability certification included for QMS and calibration record compliance
• Single-end design for use alongside a separately sourced No-Go gage
• Accepts Size 3 handle (handle not included)

Compatibility

Designed for inspection of internal 3/4-20 threaded bores. Accepts a Size 3 plug gage handle, sold separately. Compatible with ANSI and NIST-referenced thread gaging standards for 6H tolerance class applications.

Installation Notes

Thread plug gages are precision measuring instruments and should be handled by quality control or metrology personnel. Do not force the gage into a bore; the Go member should pass under hand pressure only. Store the gage in its protective case when not in use to prevent damage to the thread form. Periodic recalibration is recommended to maintain traceable accuracy, especially in high-volume inspection environments.