3-8 NPT - Go Ring Thread Gauge (JBO Johs Boss) Description

The 3-8 NPT - Go Ring Thread Gauge (JBO Johs Boss) has the following features:

• ANSI B1.1.20.1 Manufacturing Standard
• Heat-Treated Steel Material
• 8 TPI Thread Pitch
• Imperial Metric or Imperial?
• 3-8 NPT Thread Size
• NPT Thread Type
• Go Gauge Type
• JBO Johs Boss Brand/Series
• No Supplied as Pair
• Yes - Sold Separately Suitable for UKAS Calibration
• Certificate of Conformity Certification Provided

Discover more about the Ring Thread Gauges range.

Ring Thread Gauges are designed for the external measurement of male threads, such as those found on screws. Thread Gauges within this range are available in both Go and No-Go varieties.

Metric Thread Gauges

Metric Ring Thread Gauges are manufactured in coarse pitch and fine pitch varieties, and are available for use with threads from M1 to M150. Right-hand and left-hand threads are available. For more details on ISO screw threads, please see our information on ISO Metric Machine Screw Thread Dimensions.

Imperial Thread Gauges

Imperial Ring Thread Gauges are available to suit thread sizes from No.0 up to 2 1/2 inches.

Bespoke Ring Thread Gauges

Ring Thread Gauges can also be manufactured for use with less common thread types such as NPT and NPTF pipe threads, British BSW and BSF threads, and German PG threads.

What Are These Metrology Tools Used For?

These devices are used for measuring, checking and verifying threads. They are the best tool for measuring male threads as mentioned in our 'What Is Metrology?' article. For female threads such as those found on hex nuts, a Plug Gauge is required.