This basic plain hinge is suitable for lightweight standard internal residential doors a pair of hinges is adequate; however, fitting 3 hinges per door has its advantages. It will look aesthetically pleasing and from a practical viewpoint, it helps spread the load evenly and will help to overcome twisting or warping. This can sometimes happen to doors over a period of time where heat and moisture are a factor. Comes with a 10-year mechanical guarantee. Suitable for domestic use.