This is a replacement hinge for a backyard greenhouse door.  It uses 4 pieces and they are identical. The hinge screw holes are 19mm on center and 12mm in from the edge of the aluminum frame where the hinge has a little elbow to catch the frame.  I understand there are many models of greenhouses out there - this one was a common mail order 8 by 10-footer from about 10 years ago.  I'm sharing just in case this happens to work for somebody else since replacement parts are hard to find.