Supertron 171
DC Output Triode
~1926

This is an adapter type tube that allows for the connection of extra B and C batteries to the terminals on the tube shelf after removal of the jumpers. This type of tube allowed for the use of a power output tube in receivers not originally set up for one. The only marking is a small label that is badly faded, but appears to state "171 Heavy Power". Most Supertron tubes had ceramic bases, but this non-standard type uses bakelite.