Brand new in-box OS GF40 petrol four stroke engine. This was purchased for a project that required a smaller engine size and so is now surplus to needs. It cost me $1,030.00 but selling for $750 for a quick sale. Engine only taken out of plastic for photos. I have one in another aircraft and it sounds as good as the Saito but is WAY more reliable than the Saito. Has tons of power and starts with ease.