outer tube

• 外管

outer tube的用法和样例：

例句

1. This coated inner tube is closed at one end and sealed at the other end to the outer tube.
   内管的涂层是介于一端与另一端的外管的密封层里面。
2. I think the key is to see your local SAFE tube Yan lax bar may be required to go to my collar.
   我想关键还是看你们当地外管局管的严不严吧，可能按规定要本人去领的。