In one embodiment of the present invention, an oven having a flexible and retractable door is described. During the screw tightening the compressible elastomeric material sandwiched between doorknob and cylindrical part of the attachment increases the interface contact surface to take the shape of the doorknob profile. A leaf spring has an anchor portion for attachment to a subassembly wall and a spring portion flexibly coupled to the anchor portion. The mechanisms 122, 146 and 173, and the connector devices 128, 138, 166 and 172 are assembled and used as a whole within a housing, without externally exposed mechanical drive connections and without externally exposed fluid connections, between such mechanisms and devices. The cell is programmed by injecting electrons from the channel onto the floating gate by hot electron injection mechanism. The method comprises applying a tribological metal carbide reinforced amorphous hydrocarbon coating layer over either the sliding surfaces or the rolling surfaces of the bearing assembly rolling elements, but is preferably applied at least to the sliding surfaces of the rolling element.