Question about flare fitting.
 

A friend hooked me up with fittings I need for oil drain.
Brought me a 1/2npt -> 5/8 barb. He also brought me the fitting in question. It has a 5/8 barb, the other end is NPT, but slightly smaller then 1/2. The thread step is also smaller. I put the ends together and the internal diameters are the same on both fittings. Could it be a 5/8npt?

I cant find a 5/8 npt online.

I want to know what it could be and what tap and drill I would need.

I want to use the one in question because that will leave more threads in the pan wall for a better fit. Plus its flared end sits very well inside my 5/8 hose.

HA, its a 3/8npt. My AIT sensor has the identical thread. Im gonna use this in my pan.

Lock this thread up.