The SMP1210S-391K from Gowanda Electronics is a Power Inductor with Inductance 3.9 µH, Inductance Tolerance 0.1, DCR 300 milli-ohm, Saturation Current 838 mA, Temperature Operating Range -55 to 125 Degree C. Tags: Surface Mount. More details for SMP1210S-391K can be seen below.