High-Performance 4S Capable Electronic Speed Controller The Hobbywing SeaKing 90A V4 Brushless Marine Electronic Speed Controller (ESC) is designed to deliver exceptional performance for marine applications. With advanced waterproofing, built-in Bluetooth functionality, and a robust power management system, this ESC is ideal for competitive racers and RC boat enthusiasts. Engineered for reliability and convenience, it offers seamless integration with modern technology to provide a superior racing experience. About the SeaKing 90A V4 ESC Unmatched Waterproofing & Cooling Featuring an IP67 protection rating, the SeaKing 90A V4 is designed to withstand water, dust, and splashes under normal usage conditions without requiring additional waterproofing treatments. Its dual-channel water cooling system enhances heat dissipation, ensuring the ESC maintains safe operating temperatures during intense use. For added protection, the ESC includes a spark-proof circuit and capacitor overheating safeguards, extending its durability in demanding environments. Integrated Bluetooth & Data Logging The built-in Bluetooth functionality simplifies ESC programming and firmware updates. Users can connect directly to the "HW LINK V2" app on their mobile devices to adjust settings, view historical data, and monitor performance in real-time without additional hardware. The ESC's internal logging module captures up to ten minutes of operational data, enabling post-run analysis through the app for optimal tuning and maintenance. Advanced Power Management The SeaKing 90A V4 is equipped with a powerful switch-mode BEC with selectable output voltages of 6V, 7.4V, and 8.4V. This ensures compatibility with high-torque and high-voltage servos for precise and responsive control. Additionally, the Freewheeling function enhances deceleration and steering control, while the AUX external control channel allows for real-time parameter adjustments using the remote, ensuring unparalleled control during competitive races. Features: IP67 waterproof and dustproof rating Dual-channel water cooling system Built-in Bluetooth for app connectivity Internal data logging for performance tracking Spark-proof circuit for high-voltage protection Switch-mode BEC with 6V, 7.4V, and 8.4V output options Freewheeling function for enhanced deceleration and control AUX external control for real-time parameter adjustments Eleven programmable parameters for racing customization Capacitor overheating protection