This aluminum fan shroud is designed to concentrate airflow to your cooling fan. Composed of high-quality aluminum, it is lightweight and easy to drill through for a custom fit. It also comes complete with rubber flaps for higher speeds when airflow through the grille increases. Instruction sheet. Bolt-on installation. Shroud made of 16 gauge aluminum. Fits single 16" fan. 8 rubber flaps. Measures 18-3/4" tall x 20-3/4" wide x 1/2"deep. Learn more about the importance of using a fan and shroud with our radiators by reading our tech article. Radiator Cooling Performance.