A backpack containing a gravity flow water filtration system. The periphery of the table top includes a series of recessed areas, which provide for the removable placement of one or more boards having a series of removable alphanumeric characters thereon. The novel zeolite obtained provides beneficial structural features for use in petroleum refining and petrochemical processes. Two internal chambers formed by the three housing elements where one chamber contains the hydrostatic transmission and the other chamber contains the speed reducing gearing. The gate driving circuit including the shift resistors and the wirings are integrated on the insulating substrate without an additional process, thereby simplifying the manufacturing process.