Walk-behind Cut-off Saw - Concrete | CS Unitec- walk behind cut off saw ,Cut-off Saw Blades. These diamond blades are for general purpose use with the walk-behind concrete cut-off saws. There are many variations in masonry material. CS Unitec can supply the saw blade suited to the abrasiveness and hardness of your material. Please specify the application when ordering.Amazon: electric concrete sawEvolution R230DCT - 9 in Concrete Saw (Aka Circular Saw, Angle Grinder, Chop Saw, Cut Off Saw, Demo Saw, Disc Cutter, Power Cutter) - 15A Motor, No Gas - 3-1/2 In Cut - Incl Diamond Masonry Blade. $179.99. $179.