the required structural strength of the sleeve to provide sufficient structural strength of the sleeve it is typically necessary to limit perforations to only a fraction of the total surface area of the cylinder wall this reduces the flow rate and the efficiency of the filter element the sleeve can be fabricated with a helical or spiral weld to provide additional structural strength to the sleeve additionally many filter elements have pleats to increase the surface area of the filter element often the support sleeve acts as an obstruction along the length of several of these filter element pleats consequently a need still exists for an improved filter support sleeve design that permits increased open area and increases the efficiency of the filter element referring now to the drawings fig1 illustrates a metal strip 10 that is generally a flat sheet of metal shaped in substantially a long rectangular strip that is used in the construction of a support sleeve as will be described below in one embodiment the metal strip 10 is four inches wide and 48 inches in length however any other useful widths and lengths for the metal strip 10 are equally possible and are within the scope of the invention the metal.