Yes, 87 is that FBI Offense. "JK" I believe is Jacksonville, Florida location and K9, I also think is the type of testing performed at the laboratory. The 77977 is the numbers or part in question. I do think it is the case number, however, upon many attempts to the FBI; no such file, lost file, located file, but documents misplaced or lost, to finally last correspondence was destroyed in 1990.