Well i just searched the internet and found that it was a little hard to find out what AN sizes convert to in british units.

I noticed that the only other place AN sizes are mentioned on these forums they were incorrectly attributed to metric units, in otherwords -10AN means 10mm diameter, thats not the way it goes.

But the solution to the question of "what the F#&K does -08 AN mean?" is actually quite simple.

The AN number corresponds to the numerator in a fraction where the denominator is 16.

SO, -08 is equal to 8/16 or 1/2 and -10AN would be equal to 10/16, or 5/8.

So the if outside diameter of a piece of piping is 1/2 it requires a -08AN fitting.

Here is a convenient chart:

-02 AN is equal to 1/8 in.
-03 AN is equal to 3/16 in.
-04 AN is equal to 1/4 in.
-05 AN is equal to 5/16 in.
-06 AN is equal to 3/8 in.
-08 AN is equal to 1/2 in.
-10 AN is equal to 5/8 in.
-12 AN is equal to 3/4 in.
-14 AN is equal to 7/8 in.
-16 AN is equal to 1 in.
-20 AN is equal to 1 1/4 in.
-24 AN is equal to 1 1/2 in.
-32 AN is equal to 2 in.

nice, i never knew that, but i definitly knew that the -8 didnt mean 8mm. cause theres no way in hell my 20G has a 8mm oil return......

this thread rocks!

that's one thing i've always wondered when i heard you turbo guys talking ... i could never figure out what measurement an AN was..lol.
good post

hehe, I think that metric thing might have been my fault, I had the same problem and finally found out by calling summit. that was a while ago though.

why the heck don't they just call them by their sizes!!!

anyways thanks for the info!

just thought i would just let anyone who was interested know that AN Fittings are normal hardware for the Aviation industry. Everything from small 2 seater cessnas to 747 use AN fittings an if they are blue they are aluminum. This is the usual.

Hope this is helpful

Zippy1