How do I tell what "batch" my phone is before flashing back to stock?

[wes78]

I had a problem with perception where I was stuck in landscape. I flashed cognition 3.04 but I did it without flashing back to stock 2.1. I'm going to to that now, but I'm reading stuff about "batch numbers 1010 or 1012" can brick the phone if you use the Odin One-Click. Well, I don't want to brick my phone, so can someone explain what this batch thing is, and how do I tell which one I have?

Thanks

 

[Dante04SRT]

Under the battery, on the back of the phone. Look for your S/N. It should be directly below the letters "S/N".