The BS170-D27Z from onsemi is a MOSFET with Continous Drain Current 0.5 A, Drain Source Resistance 1200 to 5000 milli-ohm, Drain Source Breakdown Voltage 60 V, Gate Source Voltage -20 to 20 V, Gate Source Threshold Voltage 0.8 to 3 V. Tags: Through Hole. More details for BS170-D27Z can be seen below.