Spi 34-275-8 Plug Thread Gage 3/8-32 6H No Go

Product Description

The SPI 34-275-8 is a single-end plug thread gage used to verify that an internally threaded part does not accept an oversized or out-of-tolerance thread. Rated for 3/8-32 thread at 6H tolerance class, this No Go gage confirms rejection of threads that fall outside the specified upper limit. Made from steel, it is a standard inspection tool used by machinists, quality control technicians, and precision manufacturers. The No Go member is used after the Go gage confirms basic thread entry — together they establish a complete tolerance check for 3/8-32 internal threads. A size 2 handle is required for use but is not included with this gage.

This gage is suited for production floor inspection, incoming quality control, and toolroom verification of 3/8-32 internal threads. It applies in any setting where thread tolerance conformance must be documented, including aerospace, industrial manufacturing, and precision machining environments. The NIST-traceable calibration certification supports quality management systems that require documented measurement traceability under ANSI and NIST standards. Single-end design keeps the gage compact and straightforward for high-volume inspection tasks.

Key Features

• No Go single-end plug design checks upper thread tolerance limit for 3/8-32 internal threads
• 6H tolerance class per ANSI standards for metric-equivalent fit control
• Steel construction for durability under regular production inspection use
• NIST-traceable traceability certification included for quality system compliance
• Conforms to ANSI and NIST standards
• Size 2 handle compatible — handle sold separately

Compatibility

Designed for use with a standard size 2 plug gage handle, sold separately. Suitable as a No Go inspection member for any 3/8-32 internally threaded component requiring 6H class thread verification.

Installation Notes

Thread plug gages are installed and used by machinists or quality inspection personnel — no special tools are required beyond a compatible size 2 handle. Do not force the No Go gage into a threaded part; it should not enter a conforming thread. Store gages in a clean, dry environment and handle with care to prevent damage to the thread form. Periodic recalibration intervals should follow your facility quality management plan and applicable metrology standards.