* Whole room structure is welded by multiple square tube frames, max width of each frame is no more than 2 meters, this design makes whole structure more stable than old designs which only use square tubes at two ends of the room.
* Wall is made by glass wool sandwich board, which has the feature of anti-flaming and noise reduction, wall thickness is up to 50 mm.
* Walls are protected by high resistance rubber sheet with a max thickness of 5mm, average service time is up to 7 years.