... 1.material:good quality natural rubber 2.density: medium and hard 3.size:16--25 4 withstand high temperature Standard sponge ... pipe,steel pipe,Titanium tube,etc.Technical data Sponge Ball Technological Data SheetMaterialNatural RubberLongevityExtended Life Rubber FormulaParting ... acids, alkalis, oils, fats and solvents. high quality rubber sponge cleaning ball for pipeline cleaning