Vintage electronics Electric Trouble Finder in Wood Box 100 + years

Description

This measures to be  22" X 7" X 5"  and weights approximately 15 pounds.
No.790  is what the tag reads.  Maybe how many where made, maybe a model number
On the bottom there was a part with a number for it and the dates of May 1916 & July 1916., and can be seen in the 12th picture.
The glass on each meter is intact and without damage.
There are 3 cords that have or had a different testing device  , as seen pictures 1 & 2  and one of the 3 fell off and now is stored in the box lid, as it is the original " tail end ".
The original wood box is still in good condition even with missing a handle  & the  corner damage on the top.
The machine lifts out of the case and I included a picture of all the details.
It is a great piece of history and in rare condition for it being over  100 Years OLD !!
Thank you for your time & interest.