Mystery Pipe thread

[Glenn-BJ74]

I have a MV50 12v. air compressor, which I was intending to install a right angle elbow for the male air outlet. Here is the problem- I can't identfy the thread type of the male outlet connector which came with it. It looks like 1/4" NPT, but slightly smaller and with 27 threads per inch. So it is not 1/4" NPT (18 threads per inch or the British Standard 1/4" at 19 threads. The OD of the thread of the male fitting going into the air compressor head is just under 12 MM, but the threads do not conform to any metric thread pitches. What gives?

Any guesses what it is ?

 

[splitshot]

I've run across some of those lately (even oddballs with LH threads). Got a local hydraulic hose supply company?

 

[fj40charles]

Could it be 1/8" BSP pipe thread?

Pipe Threads for Tubes and Fittings where Pressuretight joints are made on the Threads - BS 21

 

[fj40charles]

Here is a thread that might be helpful.
European G 1/8 pipe threads? - The Home Shop Machinist & Machinist's Workshop BBS

chart of metric pipe threads:
http://mdmetric.com/tech/thddat7.htm