Test Plug, Pneumatic, Nominal Size 4 to 8 In, Min Dia 3.70 In, Max Dia 8.25 In, Max Back Air Pressure 13 PSI, Max Back Pressure 30 ft. of Head, Required Inflation Pressure 30 PSI, Deflated Size 12.00 In, Material of Construction Rubber, For Use In DWV Systems To Seal Round And Out Of Round Pipe