Major Brands TIP102-VP Darlington NPN Transistor, 100 Volt, 8 Amp, 3-Pin, TO-220 Amp B Rail, 9.28 mm H x 4.82 mm W x 10.28 mm L (Pack of 10): Amazon.com: Industrial & Scientific
2N3904 NPN Small Signal Transistor: Electronics: Amazon.com: Industrial & Scientific
NPN Transistor General Purpose Amplifier TO 92 25V 0.5A: Amazon.com: Industrial & Scientific