The outer sleeve is aluminum, inner sleeve is hot-dip galvanized seel.
外管为铝制件，内管为热镀锌钢制件。
The outer sleeve is aluminium, the inner sleeve is hot-dip galvanized seel.
外管为铝制件、内管为热镀锌钢制件。
The tank bodys are connected by pneumatic tyre unions and glass steel tubes, so they have the advantages of fine-looking, installation easily, reliable seel, and so on.
