Guys, we are talking S shaped hinge wrench, got mine years ago from SnapOn. Still to this day there are LOTS of hinges you are not going to loosen without them, Gearwrenches, none of them. You can barely do it with an S wrench sometimes.
Here's one on ebay.
Snap on Tools Wrench s Type Door Hinge Wrench 12mm S6159 Off Set Box Wrench | eBay
You will want the SAE ones of course, 1/2" and 9/16th.