Random UNIVAC item...

Hi all -- Grabbed this as it triggered both my "interesting numerical display device" and "old computer" reflexes: http://yahozna.dyndns.org/scratch/misc/univac.jpg It's labeled on the back (roughly, as things don't line up particularly well): Magtrol, Inc. DYNAMOMETER HDE-500 MODEL HD-705 SERIAL NO 511B341 TACHOMETER 811E342 MODEL SERIAL NO And riveted to the back is a placard reading "SER 2U02-2" Inside it's completely tube-based, no solid state electronics at all. Not counting the Dekatrons, there are 9 tubes in this thing, one branded "UNIVAC" on the base, the rest appear to be RCA. It looks like it contains an electronic tachometer of some sort. I can't seem to find a date code on anything. Any ideas on what this might have been used for, and how it would relate to UNIVAC? I can provide more pictures later if anyone's interested, once I get a chance to disassemble it a bit... Thanks, Josh