Disclosed is a structure of panel in flat-type CRT, which is capable of securing a stable vacuum intensity by applying sufficient tension to a face part of a panel using a straight safety band, and of effectively reducing an advance of a crack and scattering of fragments due to an external shock, by optimizing the relationship among an MMH, a CFT and an OAH, which are design factors. The invention also concerns a sustained-release solid formulation for parenteral administration comprising a homogeneous mixture of an active principle in non-dispersed state and of a biologically compatible and biodegradable excipient, in which the amount of active principle is at least 50% by weight. A method for installing a convertible electrical device cover is also disclosed including placing the convertible electrical device cover in an operative position over an electrical device so that an adapter plate may be located between the electrical device and a rear side of a base plate. The contents of data stored in the storage media are detected, and a visible identifier provided on the storage media supporting device is changed into a state corresponding to the detection result. The number of threads within the thread group is shown by way of example with three threads. The housing includes an inner mirror layer and an outer mirror layer respectively coated on the inner and outer surfaces thereof.