The BSN20BK from Nexperia is a MOSFET with Continous Drain Current 0.17 to 0.33 A, Drain Source Resistance 2100 to 5700 milliohm, Drain Source Breakdown Voltage 60 V, Gate Source Voltage -20 to 20 V, Gate Source Threshold Voltage 0.6 to 1.4 V. Tags: Surface Mount. More details for BSN20BK can be seen below.