Altech 300mA 1P Pole Thermal Magnetic Circuit Breaker, 277V ac UL. Reset Actuator Type: Toggle Switch. Overall Dimensions: 17.5 x 105.3 x 74.4mm. Overall Depth: 74.4mm. Tripping Mechanism: Thermal-Magnetic. Tripping Characteristics: Type D. Breaking Capacity at Maximum Voltage Rating: 10 kA. Overall Length: 17.5mm. Application: Heaters, High Inrush Motors, Power Supplies, Reactive Loads, Transformers. Mounting Style: DIN Rail Mount. Circuit Breaker Type: MCB. Special Features: Relatively Long Thermal Trip Delay, Very High Magnetic Trip Point. MPN: 1D03UL