Help with Datasheets

Hi, I can't find datasheet for this transistor: WB7123 (or WB7128, the marking isn't clear on the last digit) P2NA60 from ST Microelectronics. Please, help. It's from a Delta Electronics 120W psu. I want the psu schematics as well. But so far, no luck. It's marked as Delta Electronics DPS-125EB-1 A rev 03.
Thanks for your help,
Etonam.