Metric Thread Size Identifiers

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For Use With

Thread Size

Thread Pitch

Material

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Screw Size

Pipe Size

Height

Manufacturer

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Width

Thickness

Number of Identifiers

Threads per Inch

DFARS Specialty Metals

Exempt

REACH

Compliant

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Export Control Classification Number (ECCN)

EAR99

RoHS

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U.S.–Mexico–Canada Agreement (USMCA) Qualifying

Container Material

Folded Width

Folded Length

For Acme Threads per Inch

Drill Bit Size

20 Products

Grease Fitting Size Identifiers

Take the guesswork out of determining the thread type and size of a grease fitting. Screw the shank of a grease fitting into the labeled holes of these identifiers until you find the one that fits.

	For Thread Size	For Screw Size	For Pipe Size	Wd.	Ht.	Thk.		Each
Inch/Metric







	Aluminum

	Grease Fittings	NPT, SAE-LT, BSW, UNF, BSPT, BSF, Metric	External	3/16"-32, 1/4"-20, 1/4"-26, 1/4"-28, 5/16"-18, 5/16"-22, 5/16"-24, 3/8"-20, 3/8"-24, 1/2"-12, M6 × 0.75 mm, M6 × 1 mm, M8 × 1 mm, M8 × 1.25 mm, M10 × 1 mm, M10 × 1.5 mm	1/8", 1/4"	1/8, 1/4, 3/8	8 1/2"	3"	1/4"	0000000	000000

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.	Thk.	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"-14, 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	3"	39"	1/2"	3	5/16"	No	00000000	000000

Screw Size Identifiers

Metric

Find thread size, screw size, diameter, or drill bit size.

	For Thread Size	For Screw Size	For Drill Bit Size	Wd.	Ht.	Thk.		Each
Metric







	Steel

	Screws, Bolts, Threaded Rods	Metric	External	M8 × 0.75 mm, M8 × 1 mm, M8 × 1.25 mm, M9 × 0.75 mm, M9 × 1 mm, M9 × 1.25 mm, M10 × 0.75 mm, M10 × 1 mm, M10 × 1.25 mm, M10 × 1.5 mm, M11 × 0.75 mm, M11 × 1 mm, M11 × 1.5 mm, M12 × 1 mm, M12 × 1.25 mm, M12 × 1.5 mm, M12 × 1.75 mm, M14 × 1.25 mm, M14 × 1.5 mm, M14 × 2 mm	M8, M9, M10, M11, M12, M14	—	5 1/8"	5 3/8"	1/8"	000000000	000000


	Screws, Bolts, Threaded Rods, Drill Bits	Metric	External	M2 × 0.25 mm, M2 × 0.4 mm, M2.2 × 0.25 mm, M2.2 × 0.45 mm, M2.5 × 0.35 mm, M2.5 × 0.45 mm, M3 × 0.35 mm, M3 × 0.5 mm, M3.5 × 0.35 mm, M3.5 × 0.6 mm, M4 × 0.5 mm, M4 × 0.7 mm, M4.5 × 0.5 mm, M4.5 × 0.75 mm, M5 × 0.5 mm, M5 × 0.8 mm, M5.5 × 0.5 mm, M6 × 0.75 mm, M6 × 1 mm, M7 × 0.75 mm, M7 × 1 mm	M2, M2.2, M2.5, M3, M3.5, M4, M4.5, M5, M5.5, M6, M7	7/32", 52 Ga., 50 Ga., 48 Ga., 46 Ga., 45 Ga., 43 Ga., 39 Ga., 37 Ga., 32 Ga., 31 Ga., 30 Ga., 28 Ga., 25 Ga., 22 Ga., 21 Ga., 18 Ga., 16 Ga., 10 Ga., 8 Ga., 4 Ga., B, D, J	3"	5 3/8"	3/32"	000000000	00000

Thread-It Screw, Bolt, and Nut Size Identifiers

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

	For Thread Size		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"-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	000000


	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

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, mm	No. of Identifiers	Lg.	Wd.	Mfr.	Mfr. Model No.		Each
Inch/Metric







				Steel

				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, 0.3, 0.35, 0.4, 0.45, 0.5, 0.6, 0.7, 0.75, 0.8, 0.9, 1, 1.25, 1.5, 1.75, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6	52	2 3/4"	1/2"	—	—	00000000	000000


				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, 0.5, 0.6, 0.7, 0.75, 0.8, 0.9, 1, 1.25, 1.5, 1.75, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7	50	2 3/4"	1/2"	—	—	00000000	00000
				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, 0.5, 0.7, 0.75, 0.8, 0.9, 1, 1.25, 1.5, 1.75, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7	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, 0.75, 1, 1.25, 1.5, 1.75, 2, 2.5, 3, 3.5, 4, 4.5, 5, 6	28	2 3/4"	1/2"	—	—	0000000	00000


				Metric







								Steel

								Screws, Bolts, Threaded Rods, Nuts	Metric	External/Internal	—	0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 1, 1.1, 1.2, 1.25, 1.3, 1.4, 1.5, 1.6, 1.7, 1.75, 1.8, 1.9, 2, 2.5	28	2 1/2"	1/2"	Starrett	156M	0000000	00000


								Screws, Bolts, Threaded Rods, Nuts	Metric	External/Internal	—	0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 1, 1.1, 1.2, 1.25, 1.3, 1.4, 1.5, 1.6, 1.7, 1.75, 1.8, 1.9, 2, 2.5	28	2 3/4"	1/2"	—	—	0000000	00000
								Screws, Bolts, Threaded Rods, Nuts	Metric	External/Internal	—	0.4, 0.5, 0.6, 0.7, 0.75, 0.8, 0.9, 1, 1.25, 1.5, 1.75, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7	22	2 3/4"	1/2"	—	—	0000000	00000
								Screws, Bolts, Threaded Rods, Nuts	Metric	External/Internal	—	0.5, 0.75, 1, 1.1, 1.25, 1.5, 1.75, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5	27	3 1/2"	5/8"	Starrett	159M	00000000	00000




										Stainless Steel

										Screws, Bolts, Threaded Rods, Nuts	Metric Trapezoidal	External/Internal	—	2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 16, 20	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

Screw, Bolt, and Nut Size Identifiers


Inch/Metric	Metric

Use on external and internal fastener threads.

	For Screw Size	For Thread Pitch, mm	For Nut Size	Wd.	Ht.	Thk.		Each
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, 1.25, 1.5, 1.75, 2	M10, M11, M13, M17, M19, M22, M24	5 1/4"	3 3/16"	1/64"	000000000	0000

Threads per Inch and Thread Pitch Size Checkers

Inspect fasteners and verify threads with this checker. It includes three wires for each of the pitch diameters. Select the wire that best fits the threads; then calculate the pitch diameter with the equations provided.

								Wire		Container
	For Use With	For Thread Type	For Thread Location	For Threads per In.	For Thread Pitch, mm	For Acme Threads per In.	No. of Wires	Lg.	Material	Type	Material		Each
Inch/Metric



		Screws, Bolts, Threaded Rods, Pipe	NPT, UNC, UNF, Metric, Acme	External	3, 3 1/2, 4, 4 1/2, 5, 5 1/2, 6, 7, 7 1/2, 8, 9, 10, 11, 11 1/2, 12, 13, 14, 16, 18, 20, 24, 27, 28, 32, 36, 40, 44, 48	0.5, 0.6, 0.7, 0.75, 0.8, 1, 1.25, 1.5, 1.75, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6	3, 4, 5, 6, 8, 10, 12, 14, 16	48	2 3/4"	Stainless Steel	Pouch	Vinyl Plastic	000000	000000

Thread Gauges for Lug Nuts

Identify the most common bolt thread sizes.

Each







Aluminum

External/Internal	7/16"-20 1/2"-20 9/16"-18 M12 × 1.25 mm M12 × 1.5 mm M12 × 1.75 mm M14 × 1.25 mm M14 × 1.5 mm M14 × 2 mm M16 × 1.5 mm	00000000	000000