What is this plug/connector ?

[Leareth]

I have a connector that I am trying to figure out what it is called

is the size of a RCA plug.
for power supply.
just have no idea what is called.
it is NOT a RCA...

thanks.

 

[Leareth]

Seriously ?
no one knows what that is called ?

 

[Gelfin]

That is a female barrel connector.

http://en.wikipedia.org/wiki/Coaxial_DC_Power_Connectors

 

[Jaro65]

^^^^
It does look like a coax connector. But this to be used for a power supply?!