This part is a kind of semiconductor called HRP120N10K.
Function of this product has N-Channel Trench MOSFET.
Manufacturers : SemiHow
Image and pinout :

Some of the text within the PDF file :
HRP120N10K HRP120N10K 100V N-Channel Trench MOSFET FEATURES Originative New Design Superior Avalanche Rugged Technology Excellent Switching Characteristics Unrivalled Gate Charge : 65 nC (Typ.) Extended Safe Operating Area Lower RDS(ON) : 10 mΩ (Typ.) @VGS=10V 100% Avalanche Tested December 2014 BVDSS = 100 V RDS(on) typ = 10 mΩ ID = 73 A TO-220 1 23 1.Gate 2. Drain 3. Source Absolute Maximum Ratings TC=25℃ unless otherwise specified Symbol Parameter Value VDSS ID IDM VGS EAS EAR PD Drain-Source Voltage Drain Current Drain Current Drain Current – Continuous (TC = 25℃) – Continuous (TC = 100℃) – Pulsed (Note 1) Gate-Source Voltage Single Pulsed Avalanche Energy (Note 2) Repetitive Avalanche Energy (Note 1) Power Dissipation (TC = [ ... ]
HRP120N10K PDF Datasheet Download
