This is clearly a Loctal audio output pentode of American design and probably American-made. It is probably a Type 7C5 This is a Loctal version of the IO based 6V6GTY. Alternatively it could be a 14C5.
We have no details on this exhibit due to the lack of identification markings. Most valves were marked with a paint that easily rubbed off. Visual inspection reveals an oval anode cavity, an indirectly heated cathode and helical grids supported on notched rods. This is probably a pentode.
The B8B base features equi-spaced short pins protruding from the glass disc base. Location in the valve holder was by the central spigot, held in place by the metal band around the lower part of the envelope.
The wide glass tube envelope is 27 mm in diameter and, excluding the B8B base pins, is 66 mm tall.
Updated March 01, 2013. shape:wide.glass.tube construction:all.glass type:pentode age:1940.1950 base:b8b pins:8 pin: