product features：
The rotary shaft type door closer is installed inside, which is easy to install. Its shape is small and will not affect the beauty of the door. Specially designed to meet the trend of thin floor in modern buildings, the floor surface will not be damaged during installation; The central hanging automatic door shaft is most suitable for places where it is difficult to install ground springs and air drum door closers. Through interlocking with smoke sensor, it can reliably ensure the closing of fire door and the opening of flue and ventilation door. A decorative rubber sheet is attached inside for speed control and spring tensioning. Minimum embedding depth. The inner sliding base is easy to install.
