... 5.Process:forging 1.Product:Mini Excavator lower roller PC20-3 2.Warrenty:6 months3.Track ... toller effect:The function of the track roller is to convey the weight of an ... water from damaging it.4.Main Product: Track roller,Carrier roller,Sprocket,Segment,Idler,Track Link Assy,Track shoes, ... Bucket ear,Round ball,Yoke,Spring,Idler Yoke,Roller Guide,Bucket bushing,Bucket pin and so on excavator ...