As does much of the upholstery, the seat base has listing wires that need to be removed. The listing wires are what the retaining rings are crimped around and secured to the seat frame. This gives the seat its shape. Usually with years of use, moisture, and wear the listing wires are rusted to the inside of the listing. A single-edge razor blade or a pair of scissors easily extricates them for use in the new upholstery.