Duponts 9600 filter has stronger paperboard surrounding the structure which makes it more stiff than yours. Your boards tensile strength is not as good
I can feel the difference. Every allergy season is getting better and better in my home. I feel like i can always breathe. I love this product. I love that i don't have to remember to buy filters. They are always delivered in time. I feel like i always have a True fresh filter when i place them. Overall, good, no great product and great company.