AN fittings?

How do I measure the size of an AN fitting. I need to get 2 fittings that go from NPT to AN to replace the stripped out ones on my radiator and have no idea what size they are. Anybody know?

measure the outside width

If you grab a caliper and measure them in fraction form you should be able to get a rough idea...

I wouldn't see that fitting being any bigger than -6AN which is equivalent to 3/8"

Just for reference though...

-8AN = 1/2"
-6AN = 3/8"
-4AN = 1/4"
-3AN = 3/16"

*This is in reference to hose inside diameter...

Thanks for that info dev. One side is 1/2" NPT and the other side is the AN fitting and its about twice as big. Tried contacting the manufacturer but got no response...

Wowza...

Well in that case you might find this helpful:

-10AN = 5/8"
-12AN = 3/4"
-16AN = 1"
-20AN = 1-1/4"
-24AN = 1-1/2"

Again these are rough measurements not exact!

A little late but never the less
Hose sizes and fittings like that are measured in 16ths of an inch 5/8 is 10an 1 inch is 16an
Not that its needed but hydralic hoses are measure the same way if its a #20 hose its 1.25 inches.