BLUE SEA Circuit Breaker 187 SfcMt 50A The BLUE SEA Circuit Breaker 187 SfcMt 50A is a 50-amp circuit breaker designed for marine applications, featuring a compact size of 2 x 5 x 8 inches. This unit is installed in electrical systems to protect against overloads and short circuits. Compatibility & Applications Fits standard electrical panels in marine vessels. Mounts on various surfaces including bulkheads and dashboards. Replaces older circuit breakers in Blue Sea Systems installations. Pairs with 12V DC electrical systems commonly found in boats. Integrates with NMEA 2000 systems for enhanced monitoring. Compatible with sailboats and motorboats sized 20-40 ft. The unit is engineered to withstand harsh marine environments and ensure reliable circuit protection. It serves as a drop-in replacement for older Blue Sea circuit breakers, simplifying upgrades during electrical system overhauls, particularly in center-console boats where space is limited.