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For Nut Size
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.
| For Use With | For Thread Type | For Thread Location | For Thread Size | Each | |
Inch | |||||
|---|---|---|---|---|---|
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.
| For Use With | For Thread Type | For Thread Location | For Screw Size | For Thread Pitch | For Nut Size | Wd. | Ht. | Thick. | Each | |
Inch | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
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 |
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 | 0000000 |
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 |
All-in-One Identifiers
Find tube, pipe, fastener, wire, and drill bit sizes with one tool.
| For Use With (Number of Sizes) | Wd. | Ht. | Material | Each | |
Plastic | |||||
|---|---|---|---|---|---|
| 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 |
Diameter Identifiers
Measure the outside diameter of small round- and hex-shaped objects such as rods, drill bits, bolts, and tubing with this pocket-size tool. This identifier has wear-resistant etched markings.
Diameter Measuring Range | Graduation | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Inch | Metric, mm | Overall Lg. | Graduation Marks | Color | Mark Style | Color | Belt Clip | Each | |
Inch/Metric | |||||||||
Aluminum | |||||||||
| 3/32"-1 1/8" | 4-26 | 5 1/2" | 64ths, Millimeters | Blue | Etched | White | With Belt Clip | 000000 | 000000 |
Thread Gauges for Lug Nuts
Identify the most common bolt thread sizes.
| For Thread Size | For Thread Location | Material | Each | |
| 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 | External, Internal | Aluminum | 00000000 | 000000 |