This part is a kind of semiconductor called BCX12.

Function of this product has NPN Silicon AF Switching Transistor (For general AF applications High breakdown voltage).

Manufacturers : Siemens Semiconductor Group

Image and pinout :

Some of the text within the PDF file :

NPN Silicon AF Switching Transistor For general AF applications q High breakdown voltage q Low collector-emitter saturation voltage q Complementary type: BCX 13 (PNP) q 2 BCX 12 3 1 Type BCX 12 Marking BCX 12 Ordering Code Q62702-C25 Pin Configuration 1 2 3 C B E Package1) TO-92 Maximum Ratings Parameter Collector-emitter voltage Collector-base voltage Emitter-base voltage Collector current Peak collector current Base current Peak base current Total power dissipation, TC = 66 ˚C Junction temperature Storage temperature range Thermal Resistance Junction - ambient Junction - case2) Rth JA Rth JC ≤ ≤ Symbol VCE0 VCB0 VEB0 IC ICM IB IBM Ptot Tj Tstg Values 125 125 5 800 1 100 200 625 150 – 65 … + 150 Unit V mA A mA mW ˚C 200 135 K/W 1) 2) For detailed information see [ ... ]

BCX12 PDF Datasheet Download