1.Mini Excavator lower roller PC20-3 2.Material:50Mn 3.Hardness:HRC52-55 4.Warranty:6 months 5.Process:forging 1.Product:Mini Excavator ... prevent dirt, sand, and water from damaging it.4.Main Product: Track roller,Carrier roller,Sprocket,Segment,Idler,Track Link ... ,Bucket pin and so on excavator and bulldozer parts.5.Brand:Komatsu,Hitachi,Caterpillar,Kobelco,Summitomo,Hyundai,Daewoo,Volvo,Samsung, ...