The BSN20 from Diodes Incorporated is a MOSFET with Continous Drain Current 0.5 A, Drain Source Resistance 1300 to 2000 milliohm, Drain Source Breakdown Voltage 50 V, Gate Source Voltage -20 to 20 V, Gate Source Threshold Voltage 0.4 to 1.5 V. Tags: Surface Mount. More details for BSN20 can be seen below.