If you plan on running heater boxes be sure to select a fan shroud with fresh air/heater ducts and rear engine tin with fresh air/heater cut outs. If you live in a warm climate, have a custom engine, or do not plan to run heat/fresh air be sure to choose a closed fan shroud and rear engine tin.
WITH HEAT -This option includes the ducts on the front of tha fan shrouds and rear engine tin, allowing you connect your fan to your heater boxes with fresh air hoses.
WITH OUT HEAT -This option features closed fan shrouds and rear engine tin. Perfect for hiding components beneath your engine bay and eliminating the need to plug your fan shroud.