The 24S48.21FXW from Calex Manufacturing is a DC to DC Converter with Input Voltage 9 to 36 V, Output Voltage 1 48 V, Output Current 1 21 A, Output Power 1000 W, Isolation Voltage 2.25 kV. Tags: PCB Mount, Boost/Step Up. More details for 24S48.21FXW can be seen below.