Designed for applications with normal to heavy usage, the FL-4 Multi-Layer OzzyMat has (4) white layers and (1) blue layer. The white layers on the mat trap any particulate larger than 50 microns and should be peeled away once a week for optimum performance. The blue layer is the support structure that contains the microbes (Ozzy) and delivers them into the system. These microbes (Ozzy) migrate from the OzzyMat into the OzzyJuice, located in your SmartWasher tank and break down hazardous waste.