Milton® HIGHFLOWPRO® (V-Style) Industrial Steel Quick-Connect Air Coupler 3/8" NPT Milton® Industrial (V-style) High Flow/European Interchange quick-connect air fittings provide the customer with easy to install and quick disconnect high flow air couplers which can be interchangeable and are compatible with most manufacturers. High-Quality Construction The Industrial quick-connect air couplings are ideal for any high pressure.