What is the fine-grained topic of the following text: 20x48x1 Sure-Seal Poly Ring Link Economy 4 PLY Filter | Air Filters, Inc.
Air Filters Incorporated™ Sure-Seal™ 20x48x1 4-Ply MERV 8 Poly Ring Link are made with the highest quality, yellow tackified 100% virgin polyester media that is thermally sealed around a heavy duty internal wire frame. Only return the topic.
Air filter product description