The CRL Regal Adjustable Hinge is unique in design and function. The Wall Mount Model requires only two holes in the door (no cut-out). The Glass-to-Glass Model only requires four holes per Hinge (two in the door and two in the fixed panel). The Regal Hinge offers an adjustable closing angle from 0 degree to 90 degree. After the door is installed, simply loosen the Allen screw adjustment, position the door to the desired closed position, and tighten the Allen screw. You have now solved the problem of walls not meeting the door at the perfect 90 degree angle. This adjustment feature means that a single Glass-to-Glass model can accommodate angles from 90 degree to 180 degree.