Why in the hell would a company like DEWALT sell this item without DEWALT DW4706 4-1/2-Inch Backing Flange for the DW402, DW402G, and DW818?  I bought the 4 1/2 inch grinder and this blade will not function without the backing flange.  The flange is not included with the grinder and no mention of the flange is included in the requirements for this blade or the grinder.  Seriously disappointed by DEWALT.