Mai jos este o descriere de pe "The Valve Museum".
The EF800 is a special quality RF pentode that was designed for RF or IF use. It is pin compatible with the ubiquitous EF80.
The WF logo indicates that the maker was RFT in Berlin in the then East Germany.
The three wire grids are very clearly seen through the side wall of the anode.
The thin glass tube envelope is 21 mm in diameter, and excluding the B9A base pins is 54 mm tall.
