Aspen 4 is an oil-free alkylate petrol suitable for four-stroke engines of lawnmowers, rotary cultivators, snow blowers, motor boats and other equipment. Conventional gasoline contains ethanol, which absorbs moisture and can cause engine failure. Aspen alkylate petrol does not contain ethanol and is therefore ideal for use in, for example, the marine environment. To use Aspen alkylate gasoline in your two-stroke outboard engine, simply mix Aspen 4 gasoline with outboard engine oil. Choose biodegradable oil to reduce environmental impact.