The RV12P2001 is an RF pentode and looks similar to the RV12P2000. The base has side pins and a knob can be screwed into the end of the base to act as a handle.
The RV12P2001 is a true pentode and through the hole in the end wall of the anode can be seen the three wire grid.
The base with protection for the glass seal of the pins by brass sheaths embedded in the plastic. The threaded insert is for the universal handle and the square lug guides the valve correctly into the valve holder.
The white lettering is damaged but the top word is Wehrmacht - German government.
The thin glass tube envelope is 20 mm in diameter, and including the base pins is 49 mm tall.
Reference: Data-sheet. Type RV12P2001 was first introduced in 1939. See also1939 adverts.
