It says:
GENERAL ELECTRIC
MADE IN THE U.S.A.
D•C VOLTS
MODEL 8DP9V BD1
TYPE DP-9
NO. 1216247
The top line of the gauge has red numbers and goes from 0 to 3.0 with major marked increments of .2 with hash marks between increments.
The lowest line of the gauge has black numbers and goes from 0 to 150 with major marked increments of 10 with hash marks between singular increments.
It has 4 posts below the gauge.
They are marked + 3 150 300
It has a carrying strap and part of the body is a protective flap over the gauge part.
It is untested so it will be an as is sale.