Derale 17218 heavy duty 18" chrome stainless flex fan for engine cooling. Improves performance and mileage. Large surface area pulls more air at low speeds. Reinforced blade construction extends fan life. Heavy duty steel hubs. Durable stainless steel blades. Rated up to 10,000 rpm. Standard rotation. Rated at 18" in diameter and the actual measurement is 18 1/4"" in diameter. Standard rotation and 2 3/8" depth. Flange holes measure 1 3/4" to 2 1/4" and fits all popular V8 engines. Derale heavy duty flex fans provide maximum airflow at low rpms when the vehicle speed provides little or no airflow through the radiator. At higher rpms, the vehicle speed provides ample airflow and the fan blades flatten out to minimize engine loading, increasing horsepower and mileage. Fan spacer is sold seperately. NOTE: Fan chrome nose cover shown is not included. Derale 17218 heavy duty 18" chrome stainless flex fan standard rotation D17218 Check out our selection of cooling fans, water pumps, radiators, coolant recovery tanks, fan shrouds and heat protection devices. Transmission oil coolers, engine oil coolers, differential oil coolers and fuel coolers. We welcome CANADIAN customers! For ordering information, click on "Orders To Canada" at the top left side of this page. PAYMENT METHODS: PayPal, Visa, Mastercard, Discover, American Express, money orders.