Spi 23-176-1 Thread Plug Gage 1/2-13 Unc Go No Go

Product Description

The SPI 23-176-1 is a truncated taperlock thread plug gage used to verify internal thread quality on 1/2-13 UNC tapped holes. It performs both Go and No Go checks in a single set, confirming that threads fall within Class 2A tolerance limits. The gage is machined from tool steel for consistent dimensional stability and wear resistance. A 2-inch handle is included. Overall assembled length is 4.25 inches. This type of gage is standard equipment for machinists, quality control inspectors, and maintenance technicians working to UNC thread standards in production or field environments.

The SPI 23-176-1 is suited for inspection of 1/2-13 UNC threaded components in manufacturing, MRO, and mechanical assembly applications. The Go member confirms the thread can accept a mating fastener without interference. The No Go member confirms the thread has not been cut oversized. This dual-function set is appropriate wherever Class 2A fit verification is required on standard unified coarse threads in both light industrial and heavy-duty mechanical settings.

Key Features

• Verifies 1/2-13 UNC internal threads to Class 2A tolerance
• Go and No Go members included in a single set for complete thread inspection
• Truncated taperlock design for secure, repeatable seating in the handle
• Tool steel construction provides hardness and dimensional stability under repeated use
• 2-inch handle included — no separate handle purchase required
• Compact overall length of 4.25 inches suits bench and in-line inspection tasks

Compatibility

Designed for inspection of 1/2-13 UNC internally threaded components requiring Class 2A thread verification. Compatible with standard taperlock-style gage handles sized for this gage series.

Installation Notes

Thread plug gages are precision measuring instruments and should be handled accordingly. Do not force the Go member — if it does not pass under hand pressure, the thread fails. Store gages in a protective case away from other metal tooling to prevent nicking the gage members. Periodic recalibration against a traceable standard is recommended to maintain measurement accuracy over time.