The BF256B from onsemi is a Junction Field Effect Transistor (JFET) with Drain Saturation Current 6 to 13 mA, Gate Source Voltage -0.5 to -7.5 V, Gate Current 10 mA, Gate Reverse Current -5 nA, Power Dissipation 0.35 W. Tags: Through Hole. More details for BF256B can be seen below.