Precision NOGO Thread Plug Gauge Tol. 2B Unified fine STI-Thread - UNF 1.3/8 x 12

• for NO GO inspection of internal threads
• for UNF 1.3/8 x 12 when the thread system and size match the drawing or inspection plan
• for machining, maintenance, tool room, and incoming goods inspection
• for release checks after thread cutting, thread cleaning, or component repair

Note Use the gauge as an inspection instrument only and do not use it to cut, correct, or clean a thread.

• NO GO gauge function gives a clear inspection decision for the internal thread.
• The thread designation UNF 1.3/8 x 12 keeps selection tied to the drawing or inspection plan.
• Gauge use separates inspection from machining, which helps avoid accidental reworking during quality checks.
• Dedicated thread gauging supports repeatable checks in production, maintenance, and incoming goods control.

• This gauge is for internal threads only, so choose the matching opposite gauge type when the mating thread has to be inspected.

1. Confirm that UNF 1.3/8 x 12 matches the thread to be inspected.
2. Clean the internal thread and remove chips, dirt, and burrs before inspection.
3. Use the correct gauge function according to the drawing or inspection plan.
4. Gently insert the plug gauge into the internal thread without forcing the gauge.
5. Stop the inspection if resistance indicates dirt, damage, or a thread mismatch.
6. Document the inspection result before releasing or correcting the component.
7. Clean and protect the gauge after use.

• 1 piece Precision NOGO Thread Plug Gauge Tol. 2B Unified fine STI-Thread - UNF 1.3/8 x 12

• Product type: NO GO thread plug gauge
• Thread system: UNF
• Thread designation: UNF 1.3/8 x 12
• Standard: ANSI B 1.2
• Gauge function: NO GO
• Gauge target: internal threads
• Tolerance: 2B
• Direction: RH
• Package quantity: 1

What does this gauge check?

It checks internal threads for UNF 1.3/8 x 12 according to the gauge function and the inspection requirement.

Is it a cutting tool?

No, it is an inspection tool and must not be used for cutting, re-tapping, or thread cleaning.

How do you avoid selecting the wrong gauge?

Match UNF 1.3/8 x 12, the thread direction, the gauge function, and the internal or external thread target before ordering.

What should you do before gauging?

Clean the thread and gauge, then remove burrs or debris that could falsify the inspection result.

Can it inspect the mating thread?

No, use a matching ring gauge when the opposite thread type has to be inspected.

What does the gauge result depend on?

The result depends on a clean finished thread, correct gauge function, and use according to the inspection plan.

Where can you find the thread gauges catalog?

You can find the thread gauges catalog here: VG 23 catalog as PDF