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Comfort of a sofa depends on the type of spring used, both for the back of the sofa or seat pad. Spring will united with the body frame of the sofa. The spring rolls are usually made of wire with a diameter of 10 cm fitted lined with a certain distance. Or it could be made of the woven rubber straps. Or a special type of webbing jute burlap, nailed to a wooden frame around the body, and at a certain distance so as not to shift zigzag bound when someone sits on it.
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