... 3.Superior physical properties 4.Cheap price 5. At least 50 years of life Specifications: Diameters : ( 20,25) ... ,20) (32,25) (40,20) (40,20) (50,20) (50,25) (50,32) (50,40) (63,20) (63,25) (63,32) ... is simple, fast installation, economic, disassemble, maintenance3. but pressure drainage, aging resistance, long life, general and simple, reliable ... . alternative drainage iron pipe PPR concentric reducer