Popular transistors.

MMBT3904L transistor.
Pinout. Datasheet.

Marking code: 1AM
Package: SOT-23, 1-collector, 2-emitter, 3-base.
Material of transistor: Si
Polarity: NPN
Total Devise power dissipation |PD|: 0.225 Watt
Collector-base breakdown voltage |VCBO|: 60V
Collector-emitter breakdown voltage |VCEO|: 40V
Emitter-base breakdown voltage |VEBO|: 6V
Maximum collector current |Ic max|: 0.2A
Maximum junction temperature |Tj|: +150 °C
Transition frequency (ft) : 300MHz(min)
Collector Capacitance|Cc|:4,5pF(max.)
Collector-emitter saturation voltage|VCE|:300mV(IC=50mA,IB= 5mA)
Base-emitter saturation voltage|VBE|:900mV(IC=50mA,IB=5mA)
Forward current transfer ratio |hFE| : 100-300,(IC=10mA,VCE=1V),
MMBT3904L Datasheet (PDF)