As foot traffic passes over the mat, the WaterHog® surface scrapes larger particles while the Clean Stride® adhesive insert captures smaller dust & dirt. The Clean Stride® adhesive insert is comprised of 60 layers of adhesive coated film. Each layer will perform many times before it must be peeled away. Each layer is numbered to ensure one sheet at a time removal and to indicate the number of layers remaining. With two footsteps on Clean Stride® adhesive insert, over 90% of dirt particles are removed.