Regulator: Positive 3-Terminal 78xx Series
From TechWiki
3-Terminal (or an infrequent 8-terminal) POSITIVE Voltage Regulator
TO-220 Package
TO-3 Package
TO-263 Package
SOT-8 Package
Micro SMD Package
SOT-223 Package
TO-93 Package (notice that this is reversed from most other arrangements)
Datasheet
Fairchild LM78XX series regulators
NEC µPC2400A series three terminal low dropout voltage regulator