This sample pack contains our two regular hood cleaners, Hood Cleaner and Smoke House and our thicker hood cleaner Bonzi, and our Mighty Max for filters. The first two for you to see the difference between these NaOH and KOH hood cleaners, the Bonzi which is thicker and contains both hydroxides, and the Mighty Max to clean aluminum filters and the outsides of stainless appliances. These are the same products we carry separately in gallons and larger sizes so these items are concentrated and dilution ratios are the same if purchased individually. This Pack contain a limited amount of hazardous materials to be able to ship as DOT Limited Quantity. This pack of four is at a slight discount then if purchased separately.