On the other hand an fittings are flare type compression fittings and as such dont require any form of thread sealant. If you dont have a male fitting to measure an accurate measurement of the female thread id can point you to an an size.
![Xkcd Curve Fitting](https://imgs.xkcd.com/comics/curve_fitting.png)
Xkcd Curve Fitting
What is an fitting. This ultra realistic rendering of tapered vs. Note that you. An fittings use a 37 degree flare as the sealing surface. They were originally used in the aerospace industry. An fittings are a flare fitting using 37 flared tubing to form a metal metal seal. An stands for army navy.
The size specifications were established by the military back in world war ii. An fittings also known as armynavy were originally developed as a military standard that dates back as early as world war ii. The hex size depends on the fitting type the size of the threads on the other side of the fitting and even the fitting brand. Non tapered thread we just made in ms paint might clear things up. The only sure identifier is the thread size. But i only have a female fitting.
A fitting or adapter is used in pipe systems to connect straight sections of pipe or tube adapt to different sizes or shapes and for other purposes such as regulating or measuring fluid flow. The two are interchangeable in theory though this is typically not recommended due to the exacting specifications and demands of the aerospace industry. These fittings are used in plumbing to manipulate the conveyance of water gas or liquid waste in domestic or commercial environments within a system of pipes or tubes. They are similar to other 37 flared fittings such as jic which is their industrial variant. A fitting listed at 3 dash three refers to the inside diameter of the fitting for instance a 3 an would fit a metal tube outside diameter of 316 inch. Do not use an fittings with different flare type fittings.