One Person System Takes The Work Out of Brake Bleeding…Bleeding your brake or clutch line has never been easier or simpler! Revolutionary double-patented Speed Bleeder replaces the original bleeder valve in your caliper wheel cylinder with a spring-loaded one-way ball and check valve design. This unique design opens to allow the old fluid and air out, then closes automatically between pumps to prevent the old fluid and air from re-entering the line. It s a real time saver!