Ultra PowrPaks for portable restrooms and holding tanks from CPACEX offer odor control and fragrance for up to seven days in extreme conditions. The additional effervescence ensures packets will dissolve quickly and disperse evenly throughout the holding tank. They are available in five sizes to fit specific applications and climates. Use Ultra Lite in special event units or Ultra 4X in construction units, or choose the strength that works best for the application. They are biodegradable, and all formulations contain nonstaining blue dye. 419/450-6208; www.cpacex.com.