Final answer:
Gladhand couplers are the devices used to connect the service and emergency air lines from a truck or tractor to a trailer.
Step-by-step explanation:
The coupling devices used to connect the service and emergency air lines from the truck or tractor to the trailer are known as gladhand couplers. These devices are designed to interlock with each other when pressed together, creating a tight seal and allowing for the flow of air through the lines. While other items, such as suzi coils, air brake hoses, and quick release valves, are involved in the air brake system, gladhand couplers specifically refer to the interlocking connectors used at the end of the airlines that join the tractor and the trailer.