S63 -Military Study Reel - Mitsubishi Ki-57 Topsy - naval aviation reel
Japanese IJN Transport
U.S. Naval Aviation Training Division
Military Study Reels consist of 7 different range and attitude (tilt/angle) images of a plane. These reels were issued to military personnel during World War II, for recognition and range estimation of both enemy and friendly aircraft.
Study Reels (S+Number) contain recognition of different angles of the same plane, while Test Reels (T+Number) test one's knowledge of recognition of different planes.
Condition:
white front and white back,  with proper plain sleeve (no printing).  Scattered remnants of dark dis-colored dye spots in the background, barely noticeable in standard viewers.