3M™ Scott™ Safety Airline Hose and coupling assemblies are used with Scott Airline Respirators in order to maintain NIOSH approvals of the respirator. 3M™ Scott™ Safety Airline Hose and coupling assemblies are used with Scott Airline Respirators in order to maintain NIOSH approvals of the respirator. Up to 300 feet of airline hose may be used to connect the airline connection hose of the respirator to a remote breathing air supply system.