NPT Threads on Tube Connectors

Thread particulars for tube connectors most often contain three letters: NPT. NPT stands for National Pipe Thread. In contrary to other threads, the fractional number before the dash has little to do with theactual diameter, and - what's more - on a keen inspection of the thread you'll see that it is conical. For your convenience follows a table of the most common pipe threads on Harleys: