When selecting a fire hose pipe coupling, it is important to consider factors such as the size and type of hose being used, the pressure at which the system will operate, and the specific requirements of the firefighting operation. Choosing the right coupling ensures a secure and reliable connection that can withstand the demands of firefighting operations.

If the hose is connects the air conditioning evaporator, receiver/drier, and bottom connection of the condenser, It is the liquid A/C hose, the hose size is #6 5/16, the small hose in the car air conditioning system.

In addition to storz and instantaneous couplings, there are also threaded couplings, which feature male and female threads that screw together to create a tight seal. Threaded couplings are commonly used in industrial and municipal firefighting operations.