The ST-50′ s cleaning gel is made of a urethane resin developed specially for the purpose of atmospheric micro-dust control in clean rooms. Extremely effective cleaning properties are required to meet the specified standards for such applications. The ST-50 gives you the very best in stylus cleaning performance. Many stylus cleaners apply excessive force to the stylus and cantilever during the cleaning process. The DS Audio ST-50 cleans your stylus at the tracking force set on the tone arm.