The STPS40170C-Y from STMicroelectronics is a Power Diode with Forward Current 20 to 40 A, Forward Voltage 0.69 to 1 V, Reverse Current 30 uA, Repetitive Peak Reverse Voltage 170 V, Non-Repetitive Peak Forward Current 250 A. Tags: Through Hole. More details for STPS40170C-Y can be seen below.