Anyway, here's the deal. I've got a three-prong extension cord that i need to plug n2 a two-prong extension cord (all indoors by the way). I have a 3 to 2 prong adapter, and was about to plug it in; until i saw the thing about the little green metal tab and CAUTION: Shock hazard... And it's (the adapter) not going into the wall, but cord-2-cord. Is it still OK?