Porta-Pak Max Mint from Walex Products leaves a burst of fresh mint in portable restroom holding tanks. It has twice the fragrance, 50 percent more odor control and more blue color than regular Porta-Paks. It is a super-concentrated formula, conveniently packaged in easy-to-use preportioned packets that are dropped in the tank and dissolve quickly. 800/338-3155; www.walex.com.