... ,10mm,19.05mm,25.4mm,29mm,35.2mm,35.56mm roll on ball with holder are available 1) We are specialize in producing ... ,POM,PA,PMMATrackball,Ball valve,Bearing ball, Roll on ball,and so onHollow ball10mm-100mmPP,PE,HDPERoll on ball,Bearing ball,Ball valve,Floating ball,and so onRoll ...