The J201 from Central Semiconductor is a Junction Field Effect Transistor (JFET) with Drain Saturation Current 0.2 to 1.0 mA, Gate Source Voltage 40 V, Forward Transfer Admittance 0.5 mS, Gate Current 50 mA, Gate Reverse Current 1.0 nA. Tags: Through Hole. More details for J201 can be seen below.