if that's not (something), (then) I don't know what is

if that's not (something), (then) I don't know what is

Used to indicate that something is very clearly or obviously a genuine instance of something else. I'm offering a brand new washing machine for just $300! Come on, if that's not a great bargain, I don't know what is!
See also: if, know, not, what
Farlex Dictionary of Idioms.
See also:
  • all right
  • a/the feel of (something)
  • (I) wouldn't (do something) if I were you
  • a straw will show which way the wind blows
  • a slew of (something)
  • a crack at (someone or something)
  • (you) wanna make something of it?
  • all for the best
  • a thing of the past
  • a bird in the hand