UNC Plug Gauges | McMaster-Carr

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Rockwell C70

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132 Products

Go/No-Go Threaded Plug Gauges with Handle

Speed up thread tolerance checks—the handle on these gauges gives you a good grip to quickly thread and unthread go or no-go gauges. Use these gauges to make sure nuts, tapped holes, and other parts fall within tolerance. All are precisely manufactured to confirm thread fit. If the plug gauges wear down, you can insert new ones (not included) onto the taperlock handle.

A part is within tolerance if it’s easy to thread the go gauge into the part but difficult to thread the no-go gauge more than two turns.

Go/no-go gauges have both a go gauge on one end of the handle and a no-go gauge on the other to speed up tests. Go gauges check the minimum internal thread size. No-go gauges check the maximum internal thread size.

Class X Gauge

Double-Ended Taperlock

Handle

Accuracy Certificate Traceable to NIST—Gauges with an accuracy certificate traceable to NIST include verification from the manufacturer that their thread sizes are within tolerance. The certificate is also known as a certificate of compliance or a short-form certification.

Calibration Certificate Traceable to NIST—Gauges with a calibration certificate traceable to NIST were calibrated in a lab. The certificate, sometimes called a test report or long-form certificate, details the tested measurements.

For Class 2B Unified Standard Thread Fit—For inch threads, the higher the class number, the tighter the fit. Unified Standard Class 2B is standard and works for most applications.

For Thread Fit—Thread fit designates the tightness or looseness of mating threads.

	Thread Size	Thread Type	Pitch Dia. Tolerance	Hardness	Material	Features	Choose a Thread Fit		Each
Go/No-Go Gauges



		2-56	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	2366A504	0000000


		3-48	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	2366A506	000000
		4-40	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	2366A508	000000
		5-40	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	2366A511	000000
		6-32	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	2366A513	000000
		8-32	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	2366A515	000000
		10-24	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	2366A517	000000
		12-24	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	2366A519	000000
		1/4"-20	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	2366A522	00000
		5/16"-18	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	2366A524	00000
		3/8"-16	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	2366A526	00000


		7/16"-14	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	2366A528	00000
		1/2"-13	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	2366A531	000000
		5/8"-11	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	2366A533	000000
		3/4"-10	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	2366A535	000000
		7/8"-9	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	2366A537	000000
		1"-8	UNC	-0.0004" to 0.0004"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	2366A539	000000
		1 1/4"-7	UNC	-0.0004" to 0.0004"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	2366A545	000000


		Go/No-Go Gauges with Accuracy Certificate Traceable to NIST



				1-64	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	2366A225	000000


				9/16"-12	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	2366A228	000000
				1 1/8"-7	UNC	-0.0004" to 0.0004"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	2366A229	000000
				1 3/8"-6	UNC	-0.0004" to 0.0004"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	2366A231	000000
				1 1/2"-6	UNC	-0.0004" to 0.0004"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	2366A227	000000


				Go/No-Go Gauges with Calibration Certificate Traceable to NIST



						1-64	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A12	000000


						2-56	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A14	000000
						3-48	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A16	000000
						4-40	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A17	000000
						5-40	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A19	000000
						6-32	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A21	000000
						8-32	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A23	000000
						10-24	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A25	000000
						12-24	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A27	000000
						1/4"-20	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A29	000000
						5/16"-18	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A32	000000


						3/8"-16	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A34	000000
						7/16"-14	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A36	000000
						1/2"-13	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A38	000000
						9/16"-12	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	3157A336	000000
						5/8"-11	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A42	000000
3/4"-10						UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A44	000000
7/8"-9	UNC					-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A46	000000
1"-8	UNC					-0.0004" to 0.0004"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A48	000000
1 1/8"-7	UNC					-0.0004" to 0.0004"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	3157A337	000000
1 1/4"-7	UNC					-0.0004" to 0.0004"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A52	000000


1 3/8"-6	UNC					-0.0004" to 0.0004"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	3157A338	000000
1 1/2"-6	UNC					-0.0004" to 0.0004"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B , Unified Standard Class 3B	3157A54	000000

Threaded Plug Gauges

Test if internal threads fall within tolerance. These plug gauges are often used in nuts and tapped holes to confirm thread fit. For precision and accuracy, they’re manufactured to tight tolerances.

Threads are within tolerance if it’s easy to thread a go gauge but difficult to thread a no-go gauge more than two turns.

Class X Gauge

Go Gauge—Go gauges check the minimum hole diameter.

No-Go Gauge—No-go gauges check the maximum hole diameter.

For Class 2B Unified Standard Thread Fit—For inch threads, the higher the class number, the tighter the fit. Unified Standard Class 2B is standard and works for most applications.

For Thread Fit—Thread fit designates the tightness or looseness of mating threads.

	Thread Size	Thread Type	Pitch Dia. Tolerance	Hardness	Material	For Thread Fit		Each
Go Gauges



		2-56	UNC	0" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N12	000000


		4-40	UNC	0" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N13	00000
		6-32	UNC	0" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N14	00000
		8-32	UNC	0" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N15	00000
		10-24	UNC	0" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N16	00000
		1/4"-20	UNC	0" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N18	00000
		5/16"-18	UNC	0" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N21	00000
		3/8"-16	UNC	0" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N23	00000
		1/2"-13	UNC	0" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N26	00000
		5/8"-11	UNC	0" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N29	00000
		3/4"-10	UNC	0" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N32	00000


		Go Gauges with Accuracy Certificate Traceable to NIST



				2-56	UNC	0" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N102	00000


				4-40	UNC	0" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N103	00000
				6-32	UNC	0" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N104	00000
				8-32	UNC	0" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N105	00000
				10-24	UNC	0" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N106	00000
				1/4"-20	UNC	0" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N108	00000
				5/16"-18	UNC	0" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N111	00000
				3/8"-16	UNC	0" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N113	00000
				1/2"-13	UNC	0" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N116	00000
				5/8"-11	UNC	0" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N119	00000
				3/4"-10	UNC	0" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B, Unified Standard Class 3B	7968N122	00000


				No-Go Gauges



						2-56	UNC	-0.0002" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N46	00000


						4-40	UNC	-0.0002" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N47	00000
						6-32	UNC	-0.0003" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N48	00000
						8-32	UNC	-0.0003" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N49	00000
						10-24	UNC	-0.0003" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N51	00000
						1/4"-20	UNC	-0.0003" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N54	00000
						5/16"-18	UNC	-0.0003" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N57	00000
						3/8"-16	UNC	-0.0003" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N61	00000
						1/2"-13	UNC	-0.0003" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N66	00000
						5/8"-11	UNC	-0.0003" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N72	00000
						3/4"-10	UNC	-0.0003" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N75	00000


						No-Go Gauges with Accuracy Certificate Traceable to NIST



								2-56	UNC	-0.0002" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N136	00000


								4-40	UNC	-0.0002" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N137	00000
6-32								UNC	-0.0003" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N138	00000
8-32	UNC							-0.0003" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N139	00000
10-24	UNC							-0.0003" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N141	00000
1/4"-20	UNC							-0.0003" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N144	00000
5/16"-18	UNC							-0.0003" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N147	00000
3/8"-16	UNC							-0.0003" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N151	00000
1/2"-13	UNC							-0.0003" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N156	00000
5/8"-11	UNC							-0.0003" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N162	00000
3/4"-10	UNC							-0.0003" to 0"	Rockwell C70	Chrome-Plated Tool Steel	Unified Standard Class 2B	7968N165	00000

Go/No-Go Helical Insert Threaded Plug Gauges with Handle

Check that holes tapped for helical threads are within tolerance. You’ll sometimes hear these threads referred to as Screw Thread Insert (STI) threads. To speed up tests, these gauges have a go gauge on one end and a no-go gauge on the other. The double-ended taperlock handle makes them quick to thread and unthread. It also lets you swap in new plug gauges (not included) in place of worn ones.

The go gauge checks the minimum internal thread size, and the no-go gauge checks the maximum. A part is within tolerance if it’s easy to thread the go gauge but difficult to thread the no-go gauge more than two turns.

Plug Gauges with Accuracy Certificate Traceable to NIST—Gauges with an accuracy certificate traceable to NIST include verification from the manufacturer that their thread sizes are within tolerance. The certificate is also known as a certificate of compliance or a short-form certification.

Plug Gauges with Calibration Certificate Traceable to NIST—Gauges with a calibration certificate traceable to NIST were calibrated in a lab. The certificate, sometimes called a test report or long-form certificate, details the tested measurements.

								Plug Gauges with Accuracy Certificate Traceable to NIST		Plug Gauges with Calibration Certificate Traceable to NIST
	Thread Size	Thread Type	Pitch Dia. Tolerance	Hardness	Material	Features	For Thread Fit		Each		Each
Class X Gauge



		2-56	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7941N11	0000000	7941N28	0000000


		4-40	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7941N12	000000	7941N29	000000
		6-32	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7941N13	000000	7941N31	000000
		8-32	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7941N14	000000	7941N32	000000
		10-24	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7941N15	000000	7941N33	000000
		1/4"-20	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7941N17	000000	7941N35	000000
		5/16"-18	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7941N19	000000	7941N37	000000
		3/8"-16	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7941N22	000000	7941N39	000000
		1/2"-13	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7941N24	000000	7941N42	000000
		5/8"-11	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7941N26	000000	7941N44	000000
		3/4"-10	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7941N27	000000	7941N45	000000

Go/No-Go Left-Hand Threaded Plug Gauges with Handle

A go and no-go gauge in one, these gauges check that left-hand threads fall within tolerance. Use them to confirm thread fit for nuts, tapped holes, and other parts. The taperlock handle speeds up tests, giving you a good grip to thread and unthread each gauge end. It also lets you swap out worn gauges for new ones (not included) on either end.

Class X Gauge

For Class 2B Unified Standard Thread Fit—For inch threads, the higher the class number, the tighter the fit. Unified Standard Class 2B is standard and works for most applications.

For Thread Fit—Thread fit designates the tightness or looseness of mating threads.

	Thread Type	Pitch Dia. Tolerance	Hardness	Material	Features	For Thread Fit		Each
Plug Gauges with Accuracy Certificate Traceable to NIST



	6-32	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7935N31	0000000


	8-32	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7935N32	000000
	10-24	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7935N33	000000
	1/4"-20	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7935N34	000000
	5/16"-18	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7935N35	000000
	3/8"-16	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7935N36	000000
	1/2"-13	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7935N37	000000
	5/8"-11	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7935N38	000000
	3/4"-10	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7935N39	000000
	1"-8	UNC	-0.0004" to 0.0004"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7935N41	000000


	Plug Gauges with Calibration Certificate Traceable to NIST



			6-32	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7938N31	000000


			8-32	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7938N32	000000
			10-24	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7938N33	000000
			1/4"-20	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7938N34	000000
			5/16"-18	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7938N35	000000
			3/8"-16	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7938N36	000000
			1/2"-13	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7938N37	000000
			5/8"-11	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7938N38	000000
			3/4"-10	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7938N39	000000
			1"-8	UNC	-0.0004" to 0.0004"	Rockwell C70	Chrome-Plated Tool Steel	Double-Ended Taperlock Handle	Unified Standard Class 2B	7938N41	000000