The SHD218501B from Sensitron Semiconductor is a MOSFET with Continous Drain Current 35 to 45 A, Drain Source Resistance 0.027 ohm, Drain Source Breakdown Voltage 60 V, Gate Source Voltage -20 to 20 V, Gate Source Threshold Voltage 2.0 to 4.0 V. Tags: Surface Mount. More details for SHD218501B can be seen below.