... spare parts in stock 2. Slewing ring for tower crane MC310, F0/23B, H3/30 etc ... SGS certificationGOOD PAINTINGUSED FOR: QTZ80, T5020,T6018,F0/23B,T6015,H25/14 L44A1 1.6m*1 ... comes from our natlonal large-scalesteel corporations .2.The critical materials that steel,welding material etc ... heavy wall seamlesssteel pipe manufactured by Ansteel Steel Group.( 2 ) Hoisting mechanism " Jiuhe " and " Yibin " ...