USR is our specialty product designed for one particular problem. What makes USR so accepted is that this particular problem is found in every restroom with urinals. Any urinal in operation will develop offensive odors caused by the buildup of uratic salts. This uratic salts buildup in the plumbing lines takes the form of a hard, crystalline substance that smells horrible and resists all drain openers. USR safely and easily removes this buildup, eliminates the cause of the odor and cleans the fixture. For a simple observation of USR's effectiveness, put an entire egg into a glass containing USR and water. (The eggshell simulates the calcium and mineral deposits found in urinals). Notice how rapidly the USR begins its job to dissolve the shell. When complete (eggshell completely dissolved) the membrane of the egg is left intact, indicating the degree of safety.