外是玻璃管，内是扩散膜。只有这一种管吗？

外是玻璃管，内是扩散膜。只有这一种管吗？

Kết quả (Anh) 1:

Outer glass tube, is the proliferation of film. Only a tube by hand?

Kết quả (Anh) 2:

Outside is glass, inner diffusion membrane. This is the only control it?

Kết quả (Anh) 3:

Outside the glass tube, the inner is the diffusion film. Only this kind of tube?