General purpose Silicon NPN transistorUsed for switching and amplification purposes is available in Pakistan.
The NPN transistor is geared towards passing electrons from the emitter to the collector (so that conventional current flows from collector to emitter). The emitter "emits" electrons into the base, which controls the number of electrons the emitter emits. Most of the electrons emitted are "collected" by the collector, which manages to send these to the next part of the circuit.
Transistors (10 or more; according to quantity that you order)