O.S. 21XM Outboard Marine Engine. This is a high-performance water-cooled marine engine for smaller radio- controlled boats. IMPORTANT - This Engine STARTS AND RUNS IN A CLOCKWISE DIRECTION at the starter cone, any attempt to start engine in a counter-clockwise rotation may cause serious damage to the engine. Because of the clockwise rotation, the crankshaft has reverse threads. This is Not An ABC Engine.
Due to the high-performance nature of this engine
it is NOT covered by any warranty.