IW4/350 Mullard boxed black plate UU120/350 UU4 UU5 MU14

Description

Entry level for the Mullard IW4/350 which is equivalent of the Marconi Osram MU14.

The IW4/350 has same shape and design of a GZ32 with a different socket called B4.

Both come with original boxes and tested in mint condition and working order.