These reversible fans help prevent overheating in stop-and-go traffic and are designed to fit the most popular cars and trucks. They increase gas mileage and improve engine performance by freeing up the water pump pulley for more RPM. Each fan installs in minutes with simple hand tools and are available in 10", 12", 14", 15" and 16". Fans are reversible (mounts in front or back of radiator) with an ultra-thin design to fit cramped locations. They feature reinforced glass filled polypropylene blades and plastic housing for minimized weight. A universal nylon tie mounting kit is also included. Nominal fan size is based upon approximate overall assembly diameter.