One nice as-removed condition (ARC) electric RPM indicator as noted as a typed AN 5530 unit and manufactured by General Electric for the U.S. Navy. I am assuming this is WWII vintage or early post-war.

Metal data plate reads:

Typical 3 1/8" panel mount. Metal cased. Nice exceptionally crisp graphics with no bugs or dirt or crap behind the glass. No drop damage. A little dusty from storage, but otherwise good to go. This instrument has needles carded for engines 1 and 2. It's still wearing the two Cannon connector ends where it was snipped from a harness. Face is marked RPM HUNDREDS and measured in increments of 5 block markings from 0 - 45 on the instrument face. 

I have no idea what it was fitted to. We'd acquired it in a massive instrument inventory decades ago.

Big, heavy, nice. Looks like it was last overhauled 61 years ago at NAS Pensacola in 1965 as indicated by the water transfer sticker or decal on the case.

Exceptionally clean. No damage. Great core or perfect panel filler as-is. Appears to be non-radium. White markings. Crisp. That's the word to describe the graphics. 

Ships cheapest via USPS Ground Advantage or FedEx Ground unless you direct otherwise. Questions? Please ask seller.  And thanks for looking!