A.45優(yōu)質(zhì)碳素鋼 B.45鋼 C.211鋼 D.白口鐵
A.7個(gè) B.8個(gè) C.9個(gè) D.10個(gè)
A.ZG230-450 B.ZG230-420 C.ZG230-430 D.ZG230-440