Can be frustrating to hear people talk about their saws and identify them with model numbers and if you are not familiar with that make and model, you have no idea what size the power head is. Wouldn't it be nice if manufacturers would give the displacement as part of the model number? Pioneer got it right with their P-series saws with model numbers of P-41,P-51,P-61. You know right away the saw is a pro series and has a displacement of 4,5 or 6 cubic inches.