What is Sprint1x, and why am I just now seeing it?

I've updated my iPhone 5 to ios 7 and I have always gotten LTE siginals mostly in my house, occasional 3G and something I've never seen which is Sprint 1x, it is super slow, slower than 3G. I know there's Sprint O connections which is basically useless. Why hadn't sprint shown this before? I'm getting 1x where I used to get 3G siginals.

1x = Roaming. Turn it off in settings.