Pipe Thread Detectives® are precise and easy to use thread identifiers for both male and female fittings. They are especially well-suited for distinguishing between similar National, British and ISO pipe threads.

CNC machined identifiers glide on wire lanyards containing permanent, easy to read size markings which are laser etched into each stand-off. Shatterproof, color-coded gauge dividers allow recognition of each strand at a glance. NPT strands are color coated with black dividers.Thread Identifiers are equipped with a 3-3/8”(85mm) ruler. The ruler can be printed with your company or customer’s information for promotional use. For your convenience we provide extra-long wire rope for those hard to reach places, as well as loops for convenient hanging.

-NPT National Pipe Tapered Sizes: 1/8-27, 1/4-18, 3/8-18, 1/2-14, 3/4-14


For use in identifying plumbing pipe thread sizes only, including NPT/NPS/BSPT/BSPP/ISO. ALL EXPRESS AND IMPLIED WARRANTIES, INCLUDING WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE EXPRESSLY EXCLUDED. Do not force National style Pipe Thread Detective (NPS/NPT) on British style threads (BSPP/BSPT) or vice versa, as doing so will not properly identify and may damage threads. Do not use damaged threads for any applications, as doing so may result in personal injury, death or damage to property. Not for use in high pressure applications or applications involving hazardous materials, liquids, or gasses. It is highly recommended to review the instructions and flow chart at pipe.threaddetective.com.
Unit of Measure