Unity export fbx or object

I have a problem when I use the mesh extrusion extruding a tube.I want to export the tube for a FBX or object in unity.Someone give me any advice.Thanks!

Unity doesn’t support any kind of exporting assets. It’s a game engine, not a modelling tool. There are some custom scripts / plugins which allow you to export to some formats. you might find some of them on the UnifyCommunity wiki.

Here’s is an amazing .OBJ exporter, so simple works perfectly:

http://wiki.unity3d.com/index.php?title=ObjExporter