Nut Indicators | McMaster-Carr

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For Use With

Thread Type

Thread Location

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Pipe Size

Thread Pitch

Mounting Hole Diameter

Number of Mounting Holes

RoHS Compliance

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Threads per Inch

DFARS Compliance

Folded Length

Drill Bit Size

For Pipe Fitting Size

Pipe Material

Container Material

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Copper Tube Size

For Wire Gauge

Folded Width

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30 Products

Wall-Mount Thread-It Screw, Bolt, and Nut Size Identifiers

Mount to a wall for easy access, and thread your fastener into holes or onto plugs for quick and accurate size identification.

							Mounting Holes
For Use With	For Thread Type	For Thread Location	For Thread Size	Wd.	Ht.	Thick.	No. of	Hole Dia.	Fasteners Included		Each
Inch/Metric
Steel
Screws, Bolts, Threaded Rods, Nuts	UNC/UNF/Metric	External/Internal	6-32, 8-32, 10-24, 10-32, 1/4"-20, 1/4"-28, 5/16"-18, 5/16"-24, 3/8"-16, 3/8"-24, 7/16"-20, 1/2"-13, 1/2"-20, 9/16"-12, 9/16"-18, M4 × 0.7 mm, M5 × 0.8 mm, M6 × 1 mm, M7 × 1 mm, M8 × 1 mm, M8 × 1.25 mm, M10 × 1 mm, M10 × 1.25 mm, M10 × 1.5 mm, M12 × 1.25 mm, M12 × 1.5 mm, M12 × 1.75 mm, 7/16"-14	3"	39"	1/2"	3	5/16"	No	00000000	000000

Thread-It Screw, Bolt, and Nut Size Identifiers

Thread your fastener into holes or onto plugs for quick and accurate size identification.

Inch
For Use With	For Thread Type	For Thread Location	For Thread Size		Each
Steel
Screws, Bolts, Threaded Rods, Nuts	UNC/UNF	External/Internal	6-32, 6-40, 8-32, 10-24, 10-32, 1/4"-20, 1/4"-28, 5/16"-18, 5/16"-24, 3/8"-16, 3/8"-24, 7/16"-14, 7/16"-20, 1/2"-13, 1/2"-20, 9/16"-12, 9/16"-18, 5/8"-11, 5/8"-18, 3/4"-10, 3/4"-16, 1"-8, 1"-12	00000000	000000
Inch/Metric
Steel
Screws, Bolts, Threaded Rods, Nuts	UNC/UNF/Metric	External/Internal	6-32, 8-32, 10-24, 10-32, 1/4"-20, 1/4"-28, 5/16"-18, 5/16"-24, 3/8"-16, 3/8"-24, 7/16"-14, 7/16"-20, 1/2"-13, 1/2"-20, M4 × 0.7 mm, M5 × 0.8 mm, M6 × 1 mm, M7 × 1 mm, M8 × 1 mm, M8 × 1.25 mm, M10 × 1 mm, M10 × 1.25 mm, M10 × 1.5 mm, M12 × 1.25 mm, M12 × 1.5 mm, M12 × 1.75 mm	00000000	00000
Metric
Steel
Screws, Bolts, Threaded Rods, Nuts	Metric	External/Internal	M3 × 0.5 mm, M4 × 0.7 mm, M5 × 0.8 mm, M6 × 1 mm, M7 × 1 mm, M8 × 1 mm, M8 × 1.25 mm, M10 × 1 mm, M10 × 1.25 mm, M10 × 1.5 mm, M12 × 1.25 mm, M12 × 1.5 mm, M12 × 1.75 mm, M14 × 1.5 mm, M14 × 2 mm, M16 × 1.5 mm, M16 × 2 mm, M20 × 1.5 mm, M20 × 2.5 mm, M24 × 2 mm, M24 × 3 mm	00000000	00000

Screw, Bolt, and Nut Size Identifiers

Inch

Inch/Metric

Metric

Use on external and internal fastener threads.

Inch
For Use With	For Thread Type	For Thread Location	For Screw Size	For Thread Pitch	For Nut Size	Wd.	Ht.	Thick.		Each
Plastic
Screws, Bolts, Threaded Rods, Nuts	__	External/Internal	No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2", 9/16", 5/8", 3/4"	__	No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2", 9/16", 5/8"	7 1/2"	2 3/8"	1/64"	000000000	00000
Inch/Metric
Plastic
Screws, Bolts, Threaded Rods, Nuts	__	External/Internal	No. 6, No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2", 9/16", 5/8", 3/4", 1", M6, M7, M8, M10, M12, M14, M16, M18, M20, M22	__	No. 8, No. 10, 1/4", 5/16", 3/8", 7/16", 1/2", 9/16", 5/8"	9"	3 3/4"	1/64"	000000000	00000
Metric
Plastic
Screws, Bolts, Threaded Rods, Nuts	Metric	External/Internal	M6, M7, M8, M10, M12, M14, M16	1 mm, 1.25 mm, 1.5 mm, 1.75 mm, 2 mm	M10, M11, M13, M17, M19, M22, M24	5 1/4"	3 3/16"	1/64"	000000000	0000

Threads per Inch and Thread Pitch Identifiers

Determine threads per inch and thread pitch on nuts, bolts, and other fasteners. Identifiers in a variety of sizes are riveted together in a fan design—pull one out and hold it against your threads to see if it fits. Once you’ve found a match, fold identifiers in to store them in your pocket or tool bag.

						Folded
For Use With	For Thread Type	For Thread Location	For Threads per Inch	For Thread Pitch	No. of Identifiers	Lg.	Wd.	Manufacturer	Manufacturer Model No.		Each
Inch
Steel
Screws, Bolts, Threaded Rods, Nuts	UNC/UNF	External/Internal	2 1/4, 2 3/8, 2 1/2, 2 5/8, 2 3/4, 2 7/8, 3, 3 1/4, 3 1/2, 4, 4 1/2, 5, 5 1/2, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 18, 20, 24, 28	__	27	3 1/2"	7/8"	Starrett	155	00000000	000000
Screws, Bolts, Threaded Rods, Nuts	UNC/UNF	External/Internal	3 1/2, 4, 4 1/2, 5, 5 1/2, 6, 7, 8, 9, 10, 11, 11 1/2, 12, 13, 14, 15, 16, 18, 20, 22, 24, 26, 27, 28, 30, 32, 34, 36	__	28	2 1/2"	5/8"	Starrett	484	00000000	00000
Screws, Bolts, Threaded Rods, Nuts	UNC/UNF	External/Internal	4, 4 1/2, 5, 5 1/2, 6, 7, 8, 9, 10, 11, 11 1/2, 12, 13, 14, 15, 16, 18, 20, 22, 24, 26, 27, 28, 30, 32, 34, 36, 38, 40, 42	__	30	2 5/8"	5/8"	Starrett	6	00000000	00000
Screws, Bolts, Threaded Rods, Nuts	UNC/UNF	External/Internal	4, 4 1/2, 5, 5 1/2, 6, 7, 8, 9, 10, 11, 11 1/2, 12, 13, 14, 15, 16, 18, 20, 22, 24, 26, 27, 28, 30, 32, 34, 36, 38, 40, 42	__	30	2 3/4"	1/2"	__	__	0000000	00000
Screws, Bolts, Threaded Rods, Nuts	UNC/UNF	External/Internal	4, 4 1/2, 5, 5 1/2, 6, 7, 8, 9, 10, 11, 11 1/2, 12, 13, 14, 15, 16, 18, 20, 22, 24, 26, 27, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84	__	51	2 1/4"	2 1/4"	__	__	0000000	00000
Screws, Bolts, Threaded Rods, Nuts	UNC/UNF	External/Internal	4, 4 1/2, 5, 5 1/2, 6, 7, 8, 9, 10, 11, 11 1/2, 12, 13, 14, 15, 16, 18, 20, 22, 24, 26, 27, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84	__	51	3 3/8"	3/4"	Starrett	472	00000000	000000
Screws, Bolts, Threaded Rods, Nuts	UNC/UNF	External/Internal	4, 4 1/2, 5, 6, 7, 8, 9, 10, 11, 11 1/2, 12, 13, 14, 16, 18, 20, 24, 27, 28, 32, 36, 40, 44, 48, 56, 64, 72, 80	__	28	2 1/2"	5/8"	Starrett	474	00000000	00000
Screws, Bolts, Threaded Rods, Nuts	UNC/UNF	External/Internal	6, 7, 8, 9, 10, 11, 11 1/2, 12, 13, 14, 15, 16, 18, 20, 22, 24, 26, 27, 28, 30, 32, 34, 36, 38, 40, 42, 48, 50, 56, 60	__	30	2 3/4"	1/2"	__	__	000000	00000
Screws, Bolts, Threaded Rods, Nuts	UNC/UNF	External/Internal	9, 10, 11, 11 1/2, 12, 13, 14, 15, 16, 18, 20, 22, 24, 26, 27, 28, 30, 32, 34, 36, 38, 40	__	22	2 3/4"	1/2"	__	__	000000	00000
Screws, Bolts, Threaded Rods, Nuts	BSW	External/Internal	3 1/2, 4, 4 1/2, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 18, 19, 20, 22, 24, 25, 26, 28, 30, 32, 36, 40, 44, 48, 50, 60	__	30	2"	1/2"	Starrett	476	00000000	00000
Stainless Steel
Screws, Bolts, Threaded Rods, Nuts	Acme	External/Internal	1, 1 1/3, 1 1/2, 1 3/4, 2, 2 1/2, 3, 3 1/2, 4, 5, 6, 7, 8, 9, 10, 12	__	16	4 3/4"	1"	__	__	0000000	000000
Inch/Metric
Steel
Screws, Bolts, Threaded Rods, Nuts	UNC/UNF/Metric	External/Internal	4, 4 1/2, 5, 5 1/2, 6, 7, 8, 9, 10, 11, 11 1/2, 12, 13, 14, 15, 16, 18, 20, 22, 24, 26, 28, 29, 30, 32, 34, 36, 38, 40, 42	0.4 mm, 0.5 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.9 mm, 1 mm, 1.25 mm, 1.5 mm, 1.75 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm	51	2 3/4"	1/2"	__	__	0000000	00000
Screws, Bolts, Threaded Rods, Nuts	UNC/UNF/Metric	External/Internal	4, 6, 8, 10, 11, 11 1/2, 12, 13, 16, 20, 28, 32, 40, 56	0.5 mm, 0.75 mm, 1 mm, 1.25 mm, 1.5 mm, 1.75 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 6 mm	28	2 3/4"	1/2"	__	__	0000000	00000
Screws, Bolts, Threaded Rods, Nuts	BSW/Metric	External/Internal	4, 4 1/2, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 18, 19, 20, 22, 24, 25, 26, 28, 30, 32, 36, 40, 48, 60, 62	0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.9 mm, 1 mm, 1.25 mm, 1.5 mm, 1.75 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm	52	2 3/4"	1/2"	__	__	00000000	00000
Screws, Bolts, Threaded Rods, Nuts	BSW/Metric	External/Internal	4, 4 1/2, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 18, 19, 20, 22, 24, 25, 26, 28, 30, 32, 36, 40, 48, 60, 62	0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.9 mm, 1 mm, 1.25 mm, 1.5 mm, 1.75 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm	50	2 3/4"	1/2"	__	__	00000000	00000
Metric
Steel
Screws, Bolts, Threaded Rods, Nuts	Metric	External/Internal	__	0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, 0.9 mm, 1 mm, 1.1 mm, 1.2 mm, 1.25 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.75 mm, 1.8 mm, 1.9 mm, 2 mm, 2.5 mm	28	2 1/2"	1/2"	Starrett	156M	0000000	00000
Screws, Bolts, Threaded Rods, Nuts	Metric	External/Internal	__	0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, 0.9 mm, 1 mm, 1.1 mm, 1.2 mm, 1.25 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.75 mm, 1.8 mm, 1.9 mm, 2 mm, 2.5 mm	28	2 3/4"	1/2"	__	__	0000000	00000
Screws, Bolts, Threaded Rods, Nuts	Metric	External/Internal	__	0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.9 mm, 1 mm, 1.25 mm, 1.5 mm, 1.75 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm	22	2 3/4"	1/2"	__	__	0000000	00000
Screws, Bolts, Threaded Rods, Nuts	Metric	External/Internal	__	0.5 mm, 0.75 mm, 1 mm, 1.1 mm, 1.25 mm, 1.5 mm, 1.75 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm, 9.5 mm, 10 mm, 10.5 mm, 11 mm, 11.5 mm	27	3 1/2"	5/8"	Starrett	159M	00000000	00000
Stainless Steel
Screws, Bolts, Threaded Rods, Nuts	Metric Trapezoidal	External/Internal	__	2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 12 mm, 16 mm, 20 mm	12	4 3/4"	3/4"	__	__	00000000	00000

Thread Identifier Sets

Set includes calipers and gauges to identify external and internal threads.

			Container
For Use With	For Thread Type	For Thread Location	Type	Material	Includes		Each
Inch, Metric
Steel
Screws, Bolts, Threaded Rods, Nuts, Pipe	NPT, UNC, UNF, BSPT, BSPP, Metric	External/Internal	Folding Case	Plastic	Caliper, Instruction Book, Two Steel Angle Gauges, Two Steel Gauges	000000	000000

All-in-One Identifiers

Find tube, pipe, fastener, wire, and drill bit sizes with one tool.

Plastic
For Use With (Number of Sizes)	Wd.	Ht.	Material		Each
Tube (9), Tube Fittings (6), Pipe (9), Pipe Fittings (6), Screws and Bolts (20), Threaded Rods, Nuts (14), Nails (11), Wire (30), Drill Bits (21)	8 11/16"	4 1/4"	Plastic	00000000	00000
Tube (11), Tube Fittings (10), Pipe (16), Pipe Fittings (10), Screws and Bolts (20), Threaded Rods, Nuts (20), Nails (16), Wire (51), Drill Bits (50)	10 1/2"	3 1/2"	Plastic	00000000	0000