Help with indentifying of transistor

Hello guys.
I need your help with the with indentifying of this transistor.
It is on the small PCB which adjusts the rotation speed of the Dewalt 707 miter saw.
Cant find this marking anywhere.

marking
on the top - 18 508
on the bottom - BSGZ348
as I can read
look at the pic

Hello, I could not come up with this part number anywhere.

tganks for your time. it’s true.