If they are pink, square, and have bd on one side and 50 on the other and are from a gentlemen in china, then they are g2g. If they are from anywhere else they could be bunk.
I know this isn't true for everyone, but if I get lower back pain from hell when taking d-bol, I know it is legit. Of course if I weren't getting stronger and puffin up a bit too I would worry.