Obverse Design Three lines of legend across: "ATLANTIC | 54 | LOCKS" where "ATLANTIC" and "LOCKS" are in medium size letters and "54" is in large numbers. Reverse Design Blank. Metal Brass. Size and Shape Round, about 27mm in diameter, with a round hole top center. Dates Issued Unknown. Issurer Atlantic Locks. That would be the Gatun locks. Numbers Issued Pieces in collector hands include #9 and #54 (2 specimens). Rarity Rare. Manufacturer Unknown. Other Catalog Numbers Unlisted. Varieties None known. Function Tool checks were used to control access to tools. The worker would turn in the tool check in exchange for a tool. If the tool was not returned, management would know which employee had checked it out based on the number. I would appreciate from anyone who can add anything to the history of this piece. Population Count Three specimens of this variety of metal check in collector hands are known to me. Recent sales include: Check #54 (2) - Auction sale on ebay on February 22, 2007 for $21.50. Check #9 - Auction sale on ebay on January 29, 2007 for $24.37. Check #54 (1) - Auction sale on ebay on June 29, 2004 for $13.13. Note: the same number was generally issued 15 times.