substantially closes the gutter inlet 28 against entry of stormwater runoff except by flow through the filter sock 16 the overflow device 34 and filter media 18 contained in each of the filter sock 16 and overflow device 34 and by entry of excess stormwater through the gap between the filter device 12 and the upper periphery of the gutter inlet 28 and into the catch basin 30 advantageously the filtering system of the present invention enables substantially greater flexibility in the selection of varying types of filtering media without concern for the media having sufficient mass and weight to withstand undesired movement under the force of flowing stormwater runoff and in turn the filter media may be selected according to the criteria of optimizing the balance between the promotion of substantially free water flow through the device and filtration efficiency in removing silt and other debris thus the present invention enables the use of lightweight low density polymeric filter material which has not been possible with known filtration devices in turn the filtering system of the present invention is easier to handle and to install than known devices while still providing improved results it will therefore be readily understood by those persons skilled in the.