XR SeriesT 10.0 HP 306cc Horizontal Shaft Engine. This genuine 305cc Briggs and Stratton single cylinder engine offers dependable power for frequent use in demanding work environments. This engine includes a Dura-Bore cast iron cylinder sleeve for extended life. This engine includes an installed muffler, a low-oil sensor, and a fuel tank. Dura-BoreĀ® cast iron cylinder sleeve for extended life. Overhead valve design (OHV) for cooler operation and long valve life.