Aeroquip FCA0406 #4 Hose 6′ Air Brake Compressor Discharge Hose Connector. EST, MON to FRI. Brake > Electrical Connectors > Air Brake Compressor Discharge Hose Connector. Aeroquip FCA0406 #4 Hose 6. Aeroquip – FCA0406 – #4 Hose 6′ – Hose – AQP Racing Hose – 4 AN – 6 ft – Braided Stainless / Rubber – Natural – Each.