Fire Door, High Speed Door, Rapid Door manufacturer / supplier in China, offering Thermal Insulated High Speed Roller Shutter Door for Warehouse, Aviation Sliding Hangar Doors, PVC Fabric Fast Acting Rolling Shutter for Warehouse and so on.
Two high speed doors can be interlocked. When one door is open, another door will keep close. They can not open at the same time. In this way, there will be always a partition between inside and outside room, to protect inside air or hygiene.