Mercury - Helm MPR 2-Pin Weather Cap GT280 Connector Protection 86-8M0054244. Overview. Joystick-equipped boats depend on clean electrical connections, and the Helm MPR plug is no exception. The Mercury 86-8M0054244 Weather Cap protects the open 2-pin GT280 male connector used in Zeus, Axius, and Joystick Piloting for Outboards installations. It keeps the plug dry, sealed, and ready for service, preventing the moisture and debris that can create hard-to-trace faults later on.. Key Features. GT28