... acid mist,carbon dioxide and oxygen in the air pollution of water,to protect water quality,energy ... ball1mm-60mmPP,PE,ABS,POM,PA,PMMATrackball,Ball valve,Bearing ball, Roll on ball,and so onHollow ... -100mmPP,PE,HDPERoll on ball,Bearing ball,Ball valve,Floating ball,and so onRoll on ball and ... We look forward to receiving your letter! plastic floating balls for water treatment