The RMD8N40S8 from Rectron Semiconductor is a MOSFET with Continous Drain Current 8 A, Drain Source Resistance 17 to 30 milliohm, Drain Source Breakdown Voltage 40 V, Gate Source Voltage -20 to 20 V, Gate Source Threshold Voltage 1 to 2.5 V. Tags: Surface Mount. More details for RMD8N40S8 can be seen below.