A pancake engine is also known as a flat engine, because of its horizontally opposed cylinders. It is also referred to as a boxer engine, because the pistons move back and forth in a manner similar to a boxer punching. Another synonym for a pancake engine is a horizontally opposed engine, due to the positioning of the cylinders. It is also called a flat-four engine, flat-six engine, or flat-twelve engine, depending on the number of cylinders. Additionally, some car enthusiasts refer to it as a Subaru engine, since the Japanese automaker uses this type of engine in many of their vehicles. Whatever it is called, a pancake engine offers a unique combination of power and balance.