[Elecraft] Size of K2 phone jack?

[mikekopacki at verizon.net]

Anyone know the size of the phone jack in the K2?  I can't find it anywhere in the manual.

I know it's not 3/32", already wasted money on that size.

Is it 1/8", 2.5mm, 3.5mm?

Thanks!

Mike, NJ2OM