I've used the DDF Organic Sunscreen SPF 30 and like it. I see the sunscreen ingredients are zinc oxide 4%, titanium dioxide 2.5%. DDF also has an organic SPF 15 and the sunscreen ingredients are also zinc oxide 4%, titanium dioxide 2.5%.
How can two products have the exact same ingredients and percentages, yet one be SPF 30 and the other an SPF 15?