Components of the metal door weight
What is the weight of a metal front door? : Components Of The Metal Door Weight
Quote from Article entitled What is the weight of a metal front door?:
In order to lessen the door weight and to increase its stiffness special edges are made of profiled iron. The minimum number of edges installed in metal painting must be at least three: two of them are arranged vertically at the door and another one - horizontally.
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