This part is a kind of semiconductor called 2SD2012.
Function of this product has NPN Silicon Power Transistors.
Manufacturers : MCC
Image and pinout :
Some of the text within the PDF file :
MCC TM Micro Commercial Components omponents 20736 Marilla Street Chatsworth !"# $ % !"# 2SD2012 Features • High DC Current Gain: hFE(1) =100 (Min.) • Low Saturation Voltage: VCE(sat)=1.0V (Max.) • High Power Dissipation: PC=25W (TC=25OC) • Lead Free Finish/RoHS Compliant (Note1) ("P" Suffix designates RoHS Compliant. See ordering information) • Epoxy meets UL 94 V-0 flammability rating •MaMxoimisuuremSRenastitiinvigtysLevel 1 • Mounting Torgue: 5 in-lbs Maximum Symbol Rating Rating Unit VCEO Collector-Emitter Voltage 60 V VCBO Collector-Base Voltage 60 V VEBO Emitter-Base Voltage 7.0 V IC Collector Current 3.0 A IB Base Current 0.5 A PC TJ TSTG Collector power dissipation TA=25OC TC=25OC Junc [ ... ]