Belltech LEAF SPRING 84-95 TOYOTA PICKUP 3inch Suspension>Steering Dampers Its auxiliary air inlet is

Its auxiliary air inlet is used to bring in additional air from the engine compartment and can be connected to the optional Dynamic Air Scoop on the Acura TLX models (56-70016S sold separately)

As you can see

eliminating the risk of melting a trailer

A BBK Performance Mustang strut tower brace helps stiffen up the front end of any Ford Mustang by joining the front strut shock towers together

Vacuum/Boost reference capability

Belltech LEAF SPRING 84-95 TOYOTA PICKUP 3inch Suspension>Steering Dampers Its auxiliary air inlet isBy recalculating the arch of the leaf spring to provide the appropriate spring rate for a lowered ride height and utilizing the latest manufacturing techniques, Belltech's leaf springs are designed to easily lower the rear of your leaf spring equipped Sport Truck or SUV by up to 4 inches depending on application.