BC547 NPN Transistor

NPN Silicon Epitaxial Planar Transistors
These transistors are subdivided into three groups A, B, and C according to their current gain. The type BC546 is available in groups A and B, however, the types BC547 and BC548 can be supplied in all three groups. As complementary types the PNP transistors ... BC556...BC558 are recommended.
On special request, these transistors are also manufactured in the pin configuration TO-18.