Power Pentodes and Beam Tetrodes
Low Power - up to 15 watts dissipation
6V6G
EL84
EL86
Medium Power - 15 to 25 watts disipation
6L6
EL34
EL360
High Power - more than 25 watts dissipation
KT88
6550A
6146B
wot's this doing here!
6080