Double-End Plug Gauges | McMaster-Carr

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91 Products

Plug Gauges with Handle

Take go and no-go measurements with the same tool. These gauges have a go gauge on one end, a no-go gauge on the other end, and a handle with bushings. They are used for precision go/no-go measuring of hole sizes and depths, checking hole location and distance, and setting micrometers. All come with a certificate of accuracy traceable to NIST.

Check the minimum hole diameter with the go gauge end, and check the maximum hole diameter with the no-go gauge end. If the go gauge enters the hole and the no-go gauge is unable to enter, the hole is within tolerance.

Inch—Class Z

Choose a Plug Gauge Size	Increment	Go Plug Gauge Tolerance	No-Go Plug Gauge Size Tolerance	Lg.	Surface Smoothness (RMS), microinch	Hardness	Material		Each
0.0050" to 0.0755"	0.0005"	0" to 0.0001"	-0.0001" to 0"	5 1/4"	8	Rockwell C60	Tool Steel	00000000	000000
0.0760" to 0.1805"	0.0005"	0" to 0.0001"	-0.0001" to 0"	5 15/32"	8	Rockwell C60	Tool Steel	00000000	00000
0.1810" to 0.2815"	0.0005"	0" to 0.0001"	-0.0001" to 0"	6 1/8"	8	Rockwell C60	Tool Steel	00000000	00000
0.2820" to 0.4065"	0.0005"	0" to 0.0001"	-0.0001" to 0"	6 19/32"	8	Rockwell C60	Tool Steel	00000000	00000
0.4070" to 0.5105"	0.0005"	0" to 0.0001"	-0.0001" to 0"	7 3/16"	8	Rockwell C60	Tool Steel	00000000	00000
0.5110" to 0.6355"	0.0005"	0" to 0.0001"	-0.0001" to 0"	7 3/16"	8	Rockwell C60	Tool Steel	00000000	00000
0.6360" to 0.7605"	0.0005"	0" to 0.0001"	-0.0001" to 0"	7 17/32"	8	Rockwell C60	Tool Steel	00000000	00000
0.7610" to 1.0150"	0.0005"	0" to 0.0001"	-0.0001" to 0"	7 17/32"	8	Rockwell C60	Tool Steel	00000000	00000

Inch—Class X

Choose a Plug Gauge Size	Increment	Go Plug Gauge Tolerance	No-Go Plug Gauge Size Tolerance	Lg.	Surface Smoothness (RMS), microinch	Hardness	Material		Each
0.0040" to 0.0250"	0.0001"	0" to 0.00004"	-0.00004" to 0"	5 1/4"	4	Rockwell C60	Tool Steel	0000000	000000
0.0251" to 0.0750"	0.0001"	0" to 0.00004"	-0.00004" to 0"	5 1/4"	4	Rockwell C60	Tool Steel	0000000	00000
0.0751" to 0.1800"	0.0001"	0" to 0.00004"	-0.00004" to 0"	5 15/32"	4	Rockwell C60	Tool Steel	0000000	00000
0.1801" to 0.2810"	0.0001"	0" to 0.00004"	-0.00004" to 0"	6 1/8"	4	Rockwell C60	Tool Steel	0000000	00000
0.2811" to 0.4060"	0.0001"	0" to 0.00004"	-0.00004" to 0"	6 19/32"	4	Rockwell C60	Tool Steel	0000000	00000
0.4061" to 0.5100"	0.0001"	0" to 0.00004"	-0.00004" to 0"	7 3/16"	4	Rockwell C60	Tool Steel	0000000	00000
0.5101" to 0.6350"	0.0001"	0" to 0.00004"	-0.00004" to 0"	7 17/32"	4	Rockwell C60	Tool Steel	0000000	00000
0.6351" to 0.7600"	0.0001"	0" to 0.00004"	-0.00004" to 0"	7 21/32"	4	Rockwell C60	Tool Steel	0000000	00000
0.7601" to 1.0000"	0.0001"	0" to 0.00006"	-0.00006" to 0"	8 1/4"	4	Rockwell C60	Tool Steel	0000000	000000

Metric—Class Z

Choose a Plug Gauge Size	Increment	Go Plug Gauge Tolerance	No-Go Plug Gauge Size Tolerance	Lg.	Surface Smoothness (RMS), microinch	Hardness	Material		Each
0.2200 mm to 1.9100 mm	0.01 mm	0 mm to 0.0025 mm	-0.0025 mm to 0 mm	5 1/4"	8	Rockwell C60	Tool Steel	00000000	000000
1.9200 mm to 4.5700 mm	0.01 mm	0 mm to 0.0025 mm	-0.0025 mm to 0 mm	5 15/32"	8	Rockwell C60	Tool Steel	00000000	00000
4.5800 mm to 7.1400 mm	0.01 mm	0 mm to 0.0025 mm	-0.0025 mm to 0 mm	6 1/8"	8	Rockwell C60	Tool Steel	00000000	00000
7.1500 mm to 10.3100 mm	0.01 mm	0 mm to 0.0025 mm	-0.0025 mm to 0 mm	6 19/32"	8	Rockwell C60	Tool Steel	00000000	00000
10.3200 mm to 12.9500 mm	0.01 mm	0 mm to 0.0025 mm	-0.0025 mm to 0 mm	7 3/16"	8	Rockwell C60	Tool Steel	00000000	00000
12.9600 mm to 16.1300 mm	0.01 mm	0 mm to 0.0025 mm	-0.0025 mm to 0 mm	7 17/32"	8	Rockwell C60	Tool Steel	00000000	00000
16.1400 mm to 19.3000 mm	0.01 mm	0 mm to 0.0025 mm	-0.0025 mm to 0 mm	7 17/32"	8	Rockwell C60	Tool Steel	00000000	00000
19.3100 mm to 25.6500 mm	0.01 mm	0 mm to 0.0025 mm	-0.0025 mm to 0 mm	7 21/32"	8	Rockwell C60	Tool Steel	00000000	00000

Metric—Class X

Choose a Plug Gauge Size	Increment	Go Plug Gauge Tolerance	No-Go Plug Gauge Size Tolerance	Lg.	Surface Smoothness (RMS), microinch	Hardness	Material		Each
0.1010 mm to 0.3810 mm	0.001 mm	0 mm to 0.001 mm	-0.001 mm to 0 mm	5 1/4"	4	Rockwell C60	Tool Steel	0000000	0000000
0.3820 mm to 0.7620 mm	0.001 mm	0 mm to 0.001 mm	-0.001 mm to 0 mm	5 1/4"	4	Rockwell C60	Tool Steel	0000000	00000
0.7630 mm to 1.9050 mm	0.001 mm	0 mm to 0.001 mm	-0.001 mm to 0 mm	5 1/4"	4	Rockwell C60	Tool Steel	0000000	00000
1.9060 mm to 4.5720 mm	0.001 mm	0 mm to 0.001 mm	-0.001 mm to 0 mm	5 1/2"	4	Rockwell C60	Tool Steel	0000000	00000
4.5730 mm to 7.1370 mm	0.001 mm	0 mm to 0.001 mm	-0.001 mm to 0 mm	6 1/8"	4	Rockwell C60	Tool Steel	0000000	00000
7.1380 mm to 10.3120 mm	0.001 mm	0 mm to 0.001 mm	-0.001 mm to 0 mm	6 3/4"	4	Rockwell C60	Tool Steel	0000000	00000
10.3130 mm to 12.9540 mm	0.001 mm	0 mm to 0.001 mm	-0.001 mm to 0 mm	7 1/4"	4	Rockwell C60	Tool Steel	0000000	00000
12.9550 mm to 16.1290 mm	0.001 mm	0 mm to 0.001 mm	-0.001 mm to 0 mm	7 1/2"	4	Rockwell C60	Tool Steel	0000000	00000
16.1300 mm to 19.3040 mm	0.001 mm	0 mm to 0.001 mm	-0.001 mm to 0 mm	7 3/4"	4	Rockwell C60	Tool Steel	0000000	000000
19.3050 mm to 25.6540 mm	0.001 mm	0 mm to 0.001 mm	-0.001 mm to 0 mm	8 1/4"	4	Rockwell C60	Tool Steel	0000000	000000

Threaded Plug Gauges

These have a go gauge on one end and a no-go gauge on the other end. They allow you to inspect internal threads on parts. 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 X
Thread Size	Thread Type	Pitch Dia. Tolerance	Hardness	Material	Choose a For Thread Fit		Each
0-80	UNF	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	0000000
1-72	UNF	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
2-56	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
3-48	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
4-40	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
4-48	UNF	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
5-40	UNC	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
6-32	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
6-40	UNF	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
8-32	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
8-36	UNF	-0.0002" to 0.0002"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
10-24	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
10-32	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
12-24	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
1/4"-20	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
1/4"-28	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
5/16"-18	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
5/16"-24	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
3/8"-16	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
3/8"-24	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
7/16"-14	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
7/16"-20	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
1/2"-13	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
1/2"-20	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
9/16"-18	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
5/8"-11	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
5/8"-18	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
3/4"-10	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
3/4"-16	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
7/8"-9	UNC	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
7/8"-14	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
1"-8	UNC	-0.0004" to 0.0004"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
1"-12	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
1 1/8"-12	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
1 1/4"-7	UNC	-0.0004" to 0.0004"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000
1 1/4"-12	UNF	-0.0003" to 0.0003"	Rockwell C70	Chrome-Plated Tool Steel	Class 2B, Class 3B	00000000	000000

Metric

Class X
Thread Size	Pitch	Pitch Dia. Tolerance	Hardness	Material	For Thread Fit		Each
M1.6	0.35mm	-0.005" to 0.005"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	0000000
M2	0.4mm	-0.005" to 0.005"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	000000
M2.5	0.45mm	-0.005" to 0.005"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	000000
M3	0.5mm	-0.005" to 0.005"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	000000
M3.5	0.6mm	-0.005" to 0.005"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	000000
M4	0.7mm	-0.005" to 0.005"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	000000
M5	0.8mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	000000
M6	1mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	000000
M8	1mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	000000
M8	1.25mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	000000
M10	1.25mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	000000
M10	1.5mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	000000
M12	1mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	000000
M12	1.25mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	000000
M12	1.5mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	000000
M12	1.75mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	000000
M14	1.5mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	000000
M16	1.5mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	000000
M16	2mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	000000
M18	1.5mm	-0.008" to 0.008"	Rockwell C70	Chrome-Plated Tool Steel	Class 6H	000000000	000000