For hydraulic quick-connect couplings with a protruding (convex) interface, there is generally no distinction between "front" and "back" during use; the insertion method can simply be chosen based on operational requirements. However, for couplings with a flat-face interface, the connection method varies depending on the insertion orientation.
With flat-face hydraulic quick-connect couplings, it is necessary to identify the correct orientation before insertion. Generally, the curvature of the plug should align with the curvature of the sleeve; this ensures optimal sealing and safety during the connection process.
