Parliament hinges have a pivot point that is further away from the door face than a conventional butt type hinge, and are used for doors that have to clear obstacles such as architraves, or if the frame is set back with a deep reveal, and open to approx. 180°. The projection of the knuckle determines the angle to which the door will open.
Parliament hinges differ from projection hinges or broad butts with a shortened knuckle for aesthetic reasons, and because of this are often specified on restoration and heritage projects.
Parliament hinges are measured and sized between their legs, and are sold in pairs.