BSS138LT3G by Onsemi is a N-CHANNEL FET with a min DS breakdown voltage of 50V. It is used for switching applications and has a max drain current of 0.2A and max drain-source on resistance of 3.5 ohm.
NPN; Configuration: SINGLE; Surface Mount: NO; Maximum Power Dissipation (Abs): 1 W; Maximum Collector Current (IC): .8 A; Maximum Power Dissipation Ambient: .5 W;