Serpent have released a line of PTFE coated pivot balls. Made from aerospace super light aluminium they are very smooth and the range of types allows you to replace the steel versions that come as standard on the S120, S100, 733, 966 and others. The different versions include 5.8mm double straight, 5.8mm, 5.8mm long, anti-roll bar ball 3.0mm and uni 4.5mm. Read more and see photos of these pivot balls via the source link. Source: http://www.redrc.net/2012/01/serpent-ptfe-coated-pivot-balls
