6F5 RCA metal can NOS 1950”s (1.0ma Gm=1500)

6F5 RCA metal can NOS 1950”s (1.0ma Gm=1500) (strong single)

7 pins

(6F5 octal base is similar spec-wise to 7B4 loktal, Mu=100)

Zenith 10S669 radio 1941
Zenith 9S369 radio