A check valve disposed between an air pump and a section to be pressurized, is held in a closed state when the section is pressurized by said air pump, and is operated to open when the electric power is supplied to an electromagnetic solenoid. A computer program product for generating feedback for chemical mechanical polishing. The bucket may include a cast arch member extending between opposed wing members and a cast reinforcing member extending between opposed junction members adjacent said rear wall. The shaft is pivoted in the housing, and has an annular protrusion. The stabilizing member is configured to stabilize a hand of an operator at multiple positions around a periphery of the touch sensitive screen when the operator interacts with the touch sensitive screen. A heating chamber is located within the airflow chamber and includes an elongated glass body and a heating element located within the elongated glass body of the heating chamber.