Open Coil Mattresses
Open Coil Springs are the most widely used type of support system in mattresses today and are sometimes also known as a Bonnell Spring. Open Coil Sprung Mattresses are arranged in rows and connected to one another, top and bottom by a spiral helical wire with a tensioned outer rod strenthening the perimeter to keep the mattress shape. In a typical 5′ mattress this would total around 325 coils but some mattresses may have more. The higher the number of the springs, and the higher the spring gauge in the mattress, the more support it will provide. Open Coil Mattresses are usually finished with a thick layer of quilting and foam.