Vintage Triplett Model 310 analog multimeter 1950's

The item shown is a Triplett Model 310 analog multimeter, a compact device used for measuring electrical properties. Key features include: 
It measures AC and DC voltage up to 1200V.
It measures DC current.
It measures resistance and continuity.
It has overload protection.
It is portable and hand-sized.
It has a 20,000 ohms per volt DC sensitivity and 5,000 ohms per volt AC.
It comes with a protective leather case.
Introduced in 1955, this handheld analog VOM was the first to use a circuit board.

Untested