Download the BFR31 datasheet PDF.
This datasheet also includes the BFR30 variant, as both parts are published together in a single manufacturer document.
BFR30,31 MAXIMUM RATINGS
Rating Drain-Source Voltage Gate-Source Voltage Symbol VDS vgs THERMAL CHARACTERISTICS Characteristic Symbol "Total Device Dissipation, T^ = 25°C
Derate above 25°C PD.