I have installed this product, which arrived very promptly, as a replacement for an existing one of unknown make which cracked. It was vital to have a diagram of the screw holes as I was able to see that their spacing was similar to the existing holes in my door The product is indeed very similar to the replaced hinge except that it has a few mm wide strip at the end of the flange in the flag part of the hinge which is moved by the incorporated bolt. This strip, at right angle to the flange, has two short stubs which go into the side of the door. I didn’t have the holes in the door for these so I had to take the door off to create them. I needed to widen these holes and those in the door for the stubs in the movable flange, in order to get the flag part of the hinge to fit successfully using the existing screw holes in the door, as hoped when ordering. With the flag part of all three hinges inserted in the stubs in the parts of the hinges fixed to the door frame and unattached from the door, I raised the heavy door to the correct level on boards and then attached the flag parts starting with the middle one of the three hinges. Job done.
