The Ninglu Digital Speed Log Repeater IR861 is a reliable and accurate instrument designed to measure and display the speed of a vessel. It is a compact and lightweight device that can be easily installed on any vessel. The repeater is equipped with a high-precision digital speed sensor that accurately measures the speed of the vessel and displays it on a large LCD display. The repeater also features a backlight for easy viewing in low light conditions. The repeater is designed to be waterproof and dustproof, making it suitable for use in harsh marine environments. It is powered by a 12V DC power supply and is compatible with most NMEA 0183 and NMEA 2000 systems. The repeater is also equipped with a data output port for connection to other navigation systems. The Digital Speed Log Repeater is an essential tool for any vessel, providing accurate and reliable speed readings in any marine environment.