Plate
In a watch or clock the plates form the framework of the movement and in which the holes for the pivots of the train run. The plate in which the pillars are fastened permanently is called the lower or pillar plate, while the removable one is called the top plate. Watches are known as half, three-quarter and full-plate watches, according as the top-plate covers half, three-quarters or all of the lower or pillar plate. In the full-plate model the balance is mounted on the upper side of the top plate, while in the half and three-quarter plate it is mounted upon the pillar plate, thus making a thinner movement.