The Sylvania 5AS4A / 5AS4 Vacuum tube is a glass octal type used
in the power supplies of TV receivers
having high DC requirents. It requires an octal socket.
It is the same tube as a 5U4GB.
Electrical Data:
Filament Voltage .............................. 5.0 V
Filament Current .............................. 3.0 A
Substitutes ...................... 5U4GB