Manual swing doors are commonly used as entrance for buildings in the past decades. Although manual swing doors are good choices, they also have two obstacles which are hard to get resolved:

1. Hard to open huge manual swing doors

Nowadays, there is an increasing demand for higher and wider doors, but the up limit for floor spring is about 200Kgs. This limit makes it impossible to offer larger entrance design with manual swing door. At the same time, if adopt heavy-duty floor spring; the users need push hardly to open the door. It causes inconvenience for the aged and children.

2. Indoor/outdoor pressure difference

Both the indoor air conditioning system and the outdoor environment will cause pressure to the door; the pressure are different between indoor and outdoor becomes the resistance of opening the door. 

With years of innovation and design, KBB takes the lead of offering “balanced door system”. The new innovation solve the above two problems at one time：The limit of door weight could be up to 1600Kgs; and the structure of balanced door solves the pressure difference problem.