Thread Gauges with NIST Certificate

Clear All

	Certification Certification

Calibration Certificate
Traceable to NIST

	System of Measurement System of Measurement

Inch

Metric

	Thread Size Thread Size

	Thread Type Thread Type

	For Thread Fit For Thread Fit

	Gauge Type Gauge Type

No-Go

Master

	Pitch Pitch

	Class Class

	RoHS (Restriction of Hazardous Substances) RoHS (Restriction of Hazardous Substances)

RoHS Compliant

	Material Material

Steel

	DFARS (Defense Acquisition Regulations Supplement) DFARS (Defense Acquisition Regulations Supplement)

DFARS Specialty Metals
COTS-Exempt

	REACH (Registration, Evaluation, Authorization and Restriction of Chemicals) REACH (Registration, Evaluation, Authorization and Restriction of Chemicals)

REACH Compliant

	Hardness Hardness

Rockwell C60

Rockwell C70

	Pipe Size Pipe Size

	Finish Finish

Chrome Plated

	Maximum Sizes Maximum Sizes

	Surface Smoothness (RMS) Surface Smoothness (RMS)

4 microinch

8 microinch

	Minimum Sizes Minimum Sizes

357 Products

Threaded Plug Gauges with Calibration Certificate

These gauges come with a certificate of calibration traceable to NIST that states they’ve passed a test for accuracy. They allow you to inspect internal threads on parts. All have a go gauge on one end and a no-go gauge on the other end. A taperlock handle lets you quickly replace worn gauges.

Check the minimum internal thread size with the go gauge end, and check the maximum internal thread size with the no-go gauge end. 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.

Threads have different classes of fit. Thread fit designates the tightness or looseness of mating threads. For example, inch threads with a 3B fit have tighter tolerances than threads with a 2B fit.

For technical drawings and 3-D models, click on a part number.

Inch

					Class 2B		Class 3B
Thread Size	Thread Type	Pitch Dia. Tolerance	Hardness	Material		Each		Each
Class X
0-80	UNF	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	00000000	0000000	00000000	0000000
1-64	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
1-72	UNF	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
2-56	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
2-64	UNF	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
3-48	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
4-40	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
4-48	UNF	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
5-40	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
6-32	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
6-40	UNF	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
8-32	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
8-36	UNF	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
10-24	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
10-32	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
12-24	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
12-28	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
1/4"-20	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
1/4"-28	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
5/16"-18	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
5/16"-24	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
3/8"-16	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
3/8"-24	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
7/16"-14	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
7/16"-20	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
1/2"-13	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
1/2"-20	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
9/16"-18	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
5/8"-11	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
5/8"-18	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
3/4"-10	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
3/4"-16	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
7/8"-9	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
7/8"-14	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
1"-8	UNC	-0.0004" to 0.0004"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
1"-12	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
1"-14	UNS	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
1 1/8"-12	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
1 1/4"-7	UNC	-0.0004" to 0.0004"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
1 1/4"-12	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
1 1/2"-6	UNC	-0.0004" to 0.0004"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000
1 1/2"-12	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000	00000000	000000

Metric

					Class 6H
Thread Size	Pitch	Pitch Dia. Tolerance	Hardness	Material		Each
Class X
M1.6	0.35mm	-0.005" to 0.005"	Rockwell C70	Chrome-Plated Tool Steel	00000000	0000000
M2	0.4mm	-0.005" to 0.005"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000
M2.5	0.45mm	-0.005" to 0.005"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000
M3	0.5mm	-0.005" to 0.005"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000
M3.5	0.6mm	-0.005" to 0.005"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000
M4	0.7mm	-0.005" to 0.005"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000
M5	0.8mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000
M6	1mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000
M7	1mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000
M8	1mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000
M8	1.25mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000
M10	1.25mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000
M10	1.5mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000
M12	1mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000
M12	1.25mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000
M12	1.5mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000
M12	1.75mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000
M14	1.5mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000
M16	1.5mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000
M16	2mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000
M18	1.5mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	00000000	000000

Threaded Plug Gauges for NPT Pipe Threads with Calibration Certificate

Ensure the accuracy of internal NPT pipe thread measurements—these gauges come with a certificate of calibration traceable to NIST that states they’ve passed a test for accuracy. A notch on the handle indicates when the threads you’re checking are in tolerance. Gauges have a taperlock handle for quickly replacing worn gauges.

For technical drawings and 3-D models, click on a part number.

Class X
Pipe Size	Pitch Diameter Tolerance	Hardness	Material		Each
1/16	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	0000000
1/8	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000
1/4	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000
3/8	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000
1/2	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000
3/4	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000
1	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000
1 1/4	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000
1 1/2	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000
2	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000
2 1/2	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000
3	-0.0005" to 0.0005"	Rockwell C60	Tool Steel	00000000	000000
4	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000

Threaded Ring Gauges with Calibration Certificate

A certificate of calibration traceable to NIST states that these gauges have passed a test for accuracy. They’re for checking a part’s external threads to ensure they fall within tolerance.

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

Go gauges check the maximum external thread size.

No-go gauges check the minimum external thread size.

Threads have different classes of fit. Thread fit designates the tightness or looseness of the mating threads. For example, inch threads with a 3A fit have tighter tolerances than threads with a 2A fit.

For technical drawings and 3-D models, click on a part number.

Inch

					Class 2A		Class 3A
Thread Size	Thread Type	Pitch Dia. Tolerance	Hardness	Material		Each		Each
Go Gauge
Class X
0-80	UNF	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	0000000	00000000	0000000
1-64	UNC	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1-72	UNF	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
2-56	UNC	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
2-64	UNF	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
3-48	UNC	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
4-40	UNC	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
4-48	UNF	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
5-40	UNC	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
6-32	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
6-40	UNF	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
8-32	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
8-36	UNF	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
10-24	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
10-32	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
12-24	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
12-28	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1/4"-20	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1/4"-28	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
5/16"-18	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
5/16"-24	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
3/8"-16	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
3/8"-24	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
7/16"-14	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
7/16"-20	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1/2"-13	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1/2"-20	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
9/16"-18	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
5/8"-11	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
5/8"-18	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
3/4"-10	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
3/4"-16	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
7/8"-9	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
7/8"-14	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1"-8	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1"-12	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1"-14	UNS	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1 1/8"-12	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1 1/4"-7	UNC	-0.0004" to 0.0004"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1 1/4"-12	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1 1/2"-12	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1 1/2"-6	UNC	-0.0004" to 0.0004"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
No-Go Gauge
Class X
0-80	UNF	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1-64	UNC	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1-72	UNF	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
2-56	UNC	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
2-64	UNF	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
3-48	UNC	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
4-40	UNC	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
4-48	UNF	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
5-40	UNC	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
6-32	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
6-40	UNF	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
8-32	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
8-36	UNF	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
10-24	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
10-32	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
12-24	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
12-28	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1/4"-20	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1/4"-28	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
5/16"-18	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
5/16"-24	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
3/8"-16	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
3/8"-24	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
7/16"-14	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
7/16"-20	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1/2"-13	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1/2"-20	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
9/16"-18	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
5/8"-11	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
5/8"-18	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
3/4"-10	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
3/4"-16	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
7/8"-9	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
7/8"-14	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1"-8	UNC	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1"-12	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1"-14	UNS	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1 1/8"-12	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1 1/4"-7	UNC	-0.0004" to 0.0004"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1 1/4"-12	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1 1/2"-12	UNF	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
1 1/2"-6	UNC	-0.0004" to 0.0004"	Rockwell C60	Tool Steel	00000000	000000	00000000	000000

Metric

						Go Gauge		No-Go Gauge
						Class 6g		Class 6g
Thread Size	Thread Type	Pitch	Pitch Dia. Tolerance	Hardness	Material		Each		Each
Class X
M1.6	Metric	0.35 mm	-0.005mm to 0.005mm	Rockwell C60	Tool Steel	00000000	0000000	00000000	0000000
M2	Metric	0.4 mm	-0.005mm to 0.005mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
M2.5	Metric	0.45 mm	-0.005mm to 0.005mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
M3	Metric	0.5 mm	-0.005mm to 0.005mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
M3.5	Metric	0.6 mm	-0.005mm to 0.005mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
M4	Metric	0.7 mm	-0.005mm to 0.005mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
M5	Metric	0.8 mm	-0.008mm to 0.008mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
M6	Metric	1 mm	-0.008mm to 0.008mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
M7	Metric	1 mm	-0.008mm to 0.008mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
M8	Metric	1 mm	-0.008mm to 0.008mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
M8	Metric	1.25 mm	-0.008mm to 0.008mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
M10	Metric	1.25 mm	-0.008mm to 0.008mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
M10	Metric	1.5 mm	-0.008mm to 0.008mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
M12	Metric	1 mm	-0.008mm to 0.008mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
M12	Metric	1.25 mm	-0.008mm to 0.008mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
M12	Metric	1.5 mm	-0.008mm to 0.008mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
M12	Metric	1.75 mm	-0.008mm to 0.008mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
M14	Metric	1.5 mm	-0.008mm to 0.008mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
M16	Metric	1.5 mm	-0.008mm to 0.008mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
M16	Metric	2 mm	-0.008mm to 0.008mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000
M18	Metric	1.5 mm	-0.008mm to 0.008mm	Rockwell C60	Tool Steel	00000000	000000	00000000	000000

Threaded Ring Gauges for NPT Pipe Threads with Calibration Certificate

To ensure accuracy of external NPT pipe thread measurements, these gauges include a certificate of calibration traceable to NIST that states they’ve passed a test for accuracy.

For technical drawings and 3-D models, click on a part number.

Class X
Pipe Size	Pitch Diameter Tolerance	Hardness	Material		Each
1/16	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	0000000
1/8	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000
1/4	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000
3/8	-0.0002" to 0.0002"	Rockwell C60	Tool Steel	00000000	000000
1/2	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000
3/4	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000
1	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000
1 1/4	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000
1 1/2	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000
2	-0.0003" to 0.0003"	Rockwell C60	Tool Steel	00000000	000000
2 1/2	-0.0005" to 0.0005"	Rockwell C60	Tool Steel	00000000	000000
3	-0.0005" to 0.0005"	Rockwell C60	Tool Steel	00000000	000000
4	-0.0005" to 0.0005"	Rockwell C60	Tool Steel	00000000	00000000

Master Ring Gauges

Set inside micrometers, dial bore gauges, and other precision tools. These gauges come with a certificate of calibration traceable to NIST that states they’ve passed a test for accuracy.

For technical drawings and 3-D models, click on a part number.

Class Z
Choose a Size	Increment	Gauge Tolerance	Surface Smoothness (RMS), microinch	Hardness	Material		Each
0.1501" to 0.2400"	0.0001"	-0.00005" to 0.00005"	8	Rockwell C60	Tool Steel	0000000	0000000
0.2401" to 0.3650"	0.0001"	-0.00005" to 0.00005"	8	Rockwell C60	Tool Steel	0000000	000000
0.3650" to 0.5100"	0.0001"	-0.00005" to 0.00005"	8	Rockwell C60	Tool Steel	0000000	000000
0.5101" to 0.8250"	0.0001"	-0.00005" to 0.00005"	8	Rockwell C60	Tool Steel	0000000	000000
0.8251" to 1.1350"	0.0001"	-0.00006" to 0.00006"	8	Rockwell C60	Tool Steel	0000000	000000
1.1351" to 1.5100"	0.0001"	-0.00006" to 0.00006"	8	Rockwell C60	Tool Steel	0000000	000000
1.5101" to 2.0100"	0.0001"	-0.00008" to 0.00008"	8	Rockwell C60	Tool Steel	0000000	000000
2.0101" to 2.5100"	0.0001"	-0.00008" to 0.00008"	8	Rockwell C60	Tool Steel	0000000	000000
Class X
0.1501" to 0.2400"	0.0001"	-0.00002" to 0.00002"	4	Rockwell C60	Tool Steel	0000000	000000
0.2401" to 0.3650"	0.0001"	-0.00002" to 0.00002"	4	Rockwell C60	Tool Steel	0000000	000000
0.3650" to 0.5100"	0.0001"	-0.00002" to 0.00002"	4	Rockwell C60	Tool Steel	0000000	000000
0.5101" to 0.8250"	0.0001"	-0.00002" to 0.00002"	4	Rockwell C60	Tool Steel	0000000	000000
0.8251" to 1.1350"	0.0001"	-0.00003" to 0.00003"	4	Rockwell C60	Tool Steel	0000000	000000
1.1351" to 1.5100"	0.0001"	-0.00003" to 0.00003"	4	Rockwell C60	Tool Steel	0000000	000000
1.5101" to 2.0100"	0.0001"	-0.00004" to 0.00004"	4	Rockwell C60	Tool Steel	0000000	000000
2.0101" to 2.5100"	0.0001"	-0.00004" to 0.00004"	4	Rockwell C60	Tool Steel	0000000	000000