This part is a kind of semiconductor called IRFZ44.

Function of this product has Power MOSFET.

Manufacturers : Fairchild

Image and pinout :

Some of the text within the PDF file :

$GYDQFHG 3RZHU 026)(7 FEATURES ♦ Avalanche Rugged Technology ♦ Rugged Gate Oxide Technology ♦ Lower Input Capacitance ♦ Improved Gate Charge ♦ Extended Safe Operating Area ♦ 175° C Operating Temperature ♦ Lower Leakage Current: 10µA (Max.) @ VDS = 60V ♦ Lower RDS(ON): 0.020Ω (Typ.) IRFZ44 BVDSS = 60 V RDS(on) = 0.024Ω ID = 50 A TO-220 1 2 3 1.Gate 2. Drain 3. Source Absolute Maximum Ratings Symbol VDSS ID IDM VGS EAS IAR EAR dv/dt PD TJ , TSTG TL Characteristic Drain-to-Source Voltage Continuous Drain Current (TC=25°C) Continuous Drain Current (TC=100°C) Drain Current-Pulsed Gate-to-Source Voltage Single Pulsed Avalanche Energy Avalanche Current Repetitive Avalanche Energy Peak Diode Recovery dv/dt Total Power Dissipation (TC=25°C) Linear De [ ... ]

IRFZ44 PDF Datasheet Download