1,low noise, good lubrication. 2,long working life. 3, promptly deliver, warm hearted service. Gear Pump Bush feature:1.material bearing steel GCR - 15 2,Quality authentication ISO 9001:2000 3.Hardness 62-65 4.grade Greese/OilAs you requirement, such as SRL ,PS2, Alvania R12 and so on SeriesSeries 6800.6900.6100.6200.6300.6400 etc. Ring MaterialChrome Steel ,Carbon steel, Stainless steel ...