A.15mm B.20mm C.25mm D.30mm
A.皺紋鋼管護(hù)套層絞式光纜 B.層絞LAP護(hù)套光纜 C.非金屬層絞型光纜 D.鋼-塑綜合護(hù)套光纜(PSP)
A.蝶閥 B.球閥 C.旋塞閥 D.截止閥