Wondering what this means at startup

[Guest xzalt]

I just got my SMT5600 in the last few weeks, and it's been great so far but after reading posts and such here I'm wanting to go a bit deeper. So I'm hoping your knowledge can help me out. When I turn on my phone I get this message in red type on a black background:

OS 1.1.60.55

OP 1.1.0.55

Test Only

Not For Sale

The unit works fine, but I was just wondering what and if that means anything? thanks