Exact item shown, 2000 MHz (it's marked Mc because the IEEE hadn't standardized on Hz yet).  Analyzer photos show first the test setup and then the test results.  Notice that insertion loss in the pass band is about 0.2dB at 2 GHz. Filter overall length is 5-1/4 inches (~13cm), it's silver plated, there was some really gooey tape on it that I removed so I could handle it, otherwise as found.  These cavity filters generally have pretty high power ratings, I haven't found a spec for this one but the Microlab LA series 50 watts for the LA-04N filter, and this is a similar but older design. 

The NSN listing for FL2001 which is quite similar but longer gives physical data:
FL2001 — NSN 5915‑00‑824‑7163
  • Item Name: Filter, Low Pass
  • Manufacturer: Microlab/FXR (CAGE 00929)
  • Federal Supply Class: 5915 – Filters and Networks
  • Country code: 00 → U.S. origin
  • Listed in the Microlab/FXR section among low‑pass filters

Note to me: second black drawer

I normally ship within 24 hours of your order, but the post office does not always initiate tracking when I put the packages in the drop off box.  

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