Telefunken UF-14
vintage Telefunken UF14 tube, exceedingly rare in this condition.   This is a preferable tube for Neumann U47 microphone and more affordable alternative to the rare and extinct in this NOS condition VF14 tubes.
The UF14 comes close to the VF14 and but has different heating voltage .
NOS stock condition, Part of the Wunder Audio Collection. We have 1000's of these tubes and this is one of the 4 best we ever had

Photos of actual tube with marching serial number box