Another dual indicator, probably for some instrument application due to the special tube designation. The left edge is controlled by the voltage on g1 and the right edge by the voltage on g2.
Peter Magi tells us that this tube was used as a null indicator in an impedance or inductance bridge made by Siemens.
More info about the tube here:
https://www.radiomuseum.org/forumdata/upload/E82M-Teil1.pdf
https://www.radiomuseum.org/forumdata/upload/E82M-Teil2.pdf
Many thanks Peter for this information.
