hfp13n50.pdf datasheet:

Shantou Huashan Electronic Devices Co.,Ltd. HFP13N50 N-Channel Enhancement Mode Field Effect Transistor General Description These are N-Channel enhancement mode silicon gate power field effect transistors. TO-220 They are advanced power MOSFETs designed, this advanced technology has been especially tailored to minimize on-state resistance, provide superior switching performance, and withstand high energy pulse in the avalanche and commutation mode . These devices are well suited for high efficiency switch mode power supply, power factor correction, electronic lamp ballast based on half bridge. 1- G 2-D 3-S Features 13A, 500V(See Note), RDS(on)