Specifications Click here to view our Product catalog. Specifications:The PolyLast Air Filter is a cost efficient, permanent 100% polyester fiber option that fits all forced air systems. Standard Cut Sizes DPF16 1"x16"x20" 12/Ctn. DPF65 1"x16"x25" 12/Ctn. DPF20 1"x20"x20" 12/Ctn. DPF1 1"x20"x25" 12/Ctn. Bulk Roll Filter Material DPR20 1"x20"x36' 60sq. ft./Bag DPR25 1"x25"x36' 75sq. ft./Bag DPR28 1"x28"x36' 84sq. ft./Bag DPR30 1"x30"x36' 90sq. ft./Bag Also available in 2" sizes. For non-standard sizes contact factory.