A shim assembly is constructed for engaging a hinge assembly to allow operable installation of the hinge assembly in an otherwise oversized sash-frame cavity. The scale inhibitor composition can be used as a means of detecting inhibitor composition in downhole and topside oilfield treatments by means that are faster and more accurate than turbidometric measurement. The ring may be made of ferroelectric or magnetic material. The laterally flat surface of the balloon has a longitudinal groove formed thereon. An inner bag for controlling gas flow is disposed in the air bag, folded in a predetermined manner. The hollow body defines a recess which receives a nut that is adapted to protrude through a central aperture in an abrasive disc and includes an irregular surface providing an interference fit between the nut and the aperture in the disc.