The BSR58 from onsemi is a Junction Field Effect Transistor (JFET) with Drain Saturation Current 8.0 to 80.0 mA, Gate Source Voltage -40 V, Drain Source Resistance 60 Ohm, Gate Current 50 mA, Gate Reverse Current 1.0 nA. Tags: Surface Mount. More details for BSR58 can be seen below.