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 |
Pipe Thread and Thread Pitch Identifiers

In addition to checking NPT and BSPT pipe sizes, use the two included gauges for measuring thread pitch.
For Thread Type | For Pipe Size | For Gender | Wd. | Ht. | Thick. | Thread Size Identifier Material | Thread Pitch Identifier Material | Color | Each | |
BSPT, NPT | 1/8, 1/4, 3/8, 1/2, 3/4, 1, 1 1/4, 1 1/2, 2 | Female, Male | 9" | 4 1/4" | 1/4" | Plastic | Steel | Blue | 000000 | 00000 |
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 Type | For Thread Location | For Thread Size | For Screw Size | For Pipe Size | Wd. | Ht. | Thick. | Each | |
Inch, Metric | |||||||||
---|---|---|---|---|---|---|---|---|---|
Aluminum | |||||||||
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 |
Threaded Plug Gauges with Handle for Pipe Threads

Verify whether pipe fitting threads fall within tolerance. These gauges are attached to a handle, giving you a solid gripping point to thread and unthread them quickly. All are precisely manufactured to tight thread tolerances. If the gauges wear down, you can install new ones (not included) on the taperlock handle.
Gauges with NPT, NPTF, and BSPT threads have a notch to indicate whether the threads you’re checking are within tolerance. If it takes no more than one turn for the notch to sit flush against the end of your fitting, the threads are within tolerance.
Gauges with a calibration certificate traceable to NIST were calibrated in a lab. The certificate, sometimes called a test report or long-form certificate, details the tested measurements.
For technical drawings and 3-D models, click on a part number.
Gauges | Gauges with Calibration Certificate Traceable to NIST | |||||||
---|---|---|---|---|---|---|---|---|
Pipe Size | Pitch Dia. Tolerance | Hardness | Material | Features | Each | Each | ||
BSPT | ||||||||
1/8 | -0.0002" to 0.0002" | Rockwell C60 | Tool Steel | Taperlock Handle | 0000000 | 0000000 | 00000000 | 0000000 |
1/4 | -0.0002" to 0.0002" | Rockwell C60 | Tool Steel | Taperlock Handle | 0000000 | 000000 | 00000000 | 000000 |
3/8 | -0.0002" to 0.0002" | Rockwell C60 | Tool Steel | Taperlock Handle | 0000000 | 000000 | 00000000 | 000000 |
1/2 | -0.0003" to 0.0003" | Rockwell C60 | Tool Steel | Taperlock Handle | 0000000 | 000000 | 00000000 | 000000 |
Threaded Ring Gauges for Pipe Threads with Calibration Certificate

These gauges come with a certificate that’s traceable to NIST, confirming they were calibrated in a lab. The certificate, sometimes called a test report or a long-form certificate, includes the tested measurements. Use these gauges to verify whether external pipe threads are within tolerance.
Use gauges with NPT, NPTF, and BSPT threads on their own. If it takes no more than one turn for the gauge to sit flush against the end of your threads, they’re within tolerance.
For technical drawings and 3-D models, click on a part number.
Pipe Size | Thread Type | Hardness | Material | Pitch Dia. Tolerance | Each | |
BSPT Threads | ||||||
---|---|---|---|---|---|---|
1/8 | BSPT | Rockwell C60 | Tool Steel | -0.0003" to 0.0003" | 0000000 | 0000000 |
1/4 | BSPT | Rockwell C60 | Tool Steel | -0.0003" to 0.0003" | 0000000 | 000000 |
3/8 | BSPT | Rockwell C60 | Tool Steel | -0.0003" to 0.0003" | 0000000 | 000000 |
1/2 | BSPT | Rockwell C60 | Tool Steel | -0.0003" to 0.0003" | 0000000 | 000000 |
Threaded Ring Gauges for Pipe Threads

Confirm that external pipe threads are sized within tolerance. Manufactured with precision, these gauges meet tight thread tolerances themselves.
Use gauges with NPT, NPTF, and BSPT threads on their own for tests—if it takes no more than one turn for the gauge to sit flush against the end of the threads, they’re within tolerance.