Sensors are included in an inflatable packer to measure the pressure inside the packer and the distance that the outside wall of the packer moves during inflation. More specifically, the present invention provides a solderable surface-mounted card guide assembly and a staggered heatsink assembly. When the voltage level is above a first predetermined voltage, the controller generates a backup warning signal. The quantum barrier layer is a super-lattice structure including a quaternary nitride semiconductor. At least one stream is suitable for having embedded andor attached hidden data that cannot be discerned by the user when the display unit shows the document and can be retained, together with the first electronic document, in the storage unit. The lock automatically and securely affixes the cover to the container when the cover is in the closed position.