PREempt RTU Liquid Preempt Sale! Size 1L 4L This item is currently on backorder but you can still purchase it now and we'll ship as soon as more become available. PREempt™ RTU is a disinfectant as well as a cleaner for rooms and other critical environments that require cleaning and surface disinfection. Ingredients Concentration of active: 0.5% Hydrogen Peroxide. cleaning products cleansers disinfectants