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WORD OF CAUTION!!! if you want that vent to continue to work...DO NOT FORCE IT OPEN!!! Most of them get rusted closed and if you force it you will tear the hinge rivets right out of the side of the vent housing.... They typically need to be lubed with penetrating oil and left to sit for quite a while. then lube them again and let them sit..... then very gently turn the handle and gently pull if it does not BEGIN open easily....more lube more wait, if it opens a lil bit, do the open & close routine open it as far as it will go using gentle pressure then close it, then open it again, then close it...then open it and lUBE it then close it....continue until it open freely..... it is a real ***** to replace those rivets once you tear em out