AIR BRAKE SUZI COIL SET

AIR BRAKE SUZI COIL SETAir Brake Suzi Coils (also known as Suzie coils or coiled air hoses) are used to transfer compressed air from a truck (prime mover) to a trailer to operate its braking system. They are the "umbilical cords" that allow the truck and trailer to function as a single unit while maintaining the flexibility needed for turning and movement. How They Work Air Transfer: They carry compressed air that both releases the trailer's parking brakes (to allow it to

Air Brake Suzi Coils (also known as Suzie coils or coiled air hoses) are used to transfer compressed air from a truck (prime mover) to a trailer to operate its braking system.

They are the "umbilical cords" that allow the truck and trailer to function as a single unit while maintaining the flexibility needed for turning and movement. 

How They Work
Air Transfer: They carry compressed air that both releases the trailer's parking brakes (to allow it to move) and applies the service brakes (to slow it down).
Coiled Design: The "curly" shape allows the hoses to stretch and retract as the vehicle articulates (turns or moves over bumps), preventing them from dragging on the ground or snapping under tension.
Fail-Safe Safety: If the trailer accidentally disconnects, the air hoses snap. This sudden loss of air pressure causes the trailer's emergency brakes to lock automatically, bringing it to a stop.

Suzi coil sets are almost always colour-coded to prevent incorrect connections: 
Red (Emergency/Supply Line): Supplies a constant flow of air to fill the trailer's air tanks. If this line loses pressure, the emergency brakes engage.
Blue (Service Line): Only carries air when the driver presses the brake pedal. This signal tells the trailer's brakes to apply in sync with the truck.

The long tail (usually 1 metre of straight hose before the coil starts) is specifically designed for trucks where the air connections are elevated. It provides extra reach to bridge the gap from a high mounting point (like an A-frame or pogo stick behind the cab) down to the trailer without putting excessive strain on the coiled section.