Blue Sea Systems 285 Series Circuit Breaker Surface Mount 25A-150A

Max Voltage: 48V DC (No AC)
Interrupt Capacity: 3000A @ 48V
Circuit Breaker Type: Thermal, Bi-metal
Operating Temperature Range: -40C to 85C
Ignition Protected: Yes, SAE J1171
Ingress Protection: IP67 - waterproof immersion up to 1M for 30 minutes

Mounting Style: Surface Mount
Ring Terminal: 1/4in (M6)
Mounting Holes: 2
Mounting Screw Size: 1/4in (M6)

285 series circuit breakers are a thermal style breaker. They are produced with a specified bi-metal. When current travels through this metal it heats up, the metal thickness determines the amperage rating. When the metal hits a certain temperature it warps and trips the lever in the circuit breaker. Since these circuit breakers are thermal it doesn't matter which direction the current flows, the bi-metal will heat up either way. So even though there is a "Bat" and "Aux" label on the plastic you can install your wires either way.