How much did you pay for them and do you still have the box?
Second what model/brand are they? If Revision Eyewear $90-100 is about right for them. If cheaper, then they are suspect.
Look for a ANSI Z87 stamp on them, also look for a moulded date stamp on the frames. I'm not in town at the moment but if they are Revision Eyewear I can compare them against my brothers model.
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE