Reverse Side is Graphic Art - Not an Actual Scanned Image

Obverse Design Metal check has four lines of legends written horizontally and left-justified near the left end of the check. The first line is starts above the small hole and says "G.E. VRADENBURG.". The second line starts to the right of the small hole and says "F.A.B." (an abbreviation for Fleet Air Base). The third line starts to the right of the small hole and says "COCO SOLO.". The fourth or bottom line starts under the small hole and says "CANAL ZONE.". On the right end of the check, written perpendicular to the other legends is the legend "A & R".
Reverse Design Blank.
Metal Brass Size and Shape About rectangular, 76 mm wide and 26 mm high. Small round hole on the left side of the obverse.
Dates Issued Sometime between 1931 and 1939.
Issuer Coco Solo Fleet Air Base.
Numbers Issued Not numbered.
Rarity Very Rare. Manufacturer Unknown. Other Catalog Numbers Rulau CZ 8.
Varieties None known.
Function Unknown. This may have been a tool check. The "G.E. VRADENBURG" apparently is the name of an employee. I am not sure what the "A & R" abbreviation meant. I would appreciate e-mail from anyone who can add anything to the history of this piece.
Population Count Only one specimen in collector hands is known to me. I do not know of any recent sales.
Notes Coco Solo in the Panama Canal Zone was established in July 1917. It commissioned as NAS (Naval Air Station) on 6 May 1918 for patrol operations by seaplane and LTA. The site placed in reserve in 1922, but became a FAB (Fleet Air Base) on 1 July 1931. Then in 30 September 1939 it was redesignated an NAS (Naval Air Station). Following active use during World War II operations ceased on 15 February 1950 and final disestablishment came on 1 July 1950.