Over 125,000 vehicle owners can't be wrong! Increase your vehicle's MPG up to 20% & save! Introducing the new FD-47 Pro Series by Fuel Doctor! This 4th generation power conditioner features higher grade electronics, a new sleek design & the capability to work on a much wider array of vehicles so more people can save like never before. Fuel Doctor works to help reduce electrical interference/ noise/ surges/spikes in your vehicle's power system, including fuel injection systems, to improve engine efficiency. By enhancing the firing of your engine, power is boosted and gas mileage is increased which saves you money. It also helps you reduce your carbon footprint! It's approved by a certified EPA test facility and installs in seconds - just plug it into your vehicle's 12V lighter socket and drive! It really works and won't damage your vehicle. For vehicles 24 months of age or older. Not for use with hybrids or electric vehicles. This is a customer return. Customer returned items have a 7 day return policy.