Knee Map Holder US Navy T93-H-202500 1948 AR-234 According to our friends at

According to our friends at DeutscheLuftwaffe:

two remote controls are provided and

housed in a black aluminum case secured to the aircraft’s instrument panel

It is the basic reference book for aircraft radio operators in the performance of their duties

Here is a WWII-era Bombardiers' Information File published by the US Army Air Force May 1945

Knee Map Holder US Navy T93-H-202500 1948 AR-234 According to our friends atThis is an original Knee Map Holder as used by some pilots of the US Navy post WWII. According to the accompanying bulletin, the board is strapped to the pilots left leg with the map inserted between the plastic panel and the aluminum frame. There is a compass rose mounted to a flexible arm that can be positioned anywhere over the map. A small spring loaded chain can be extended around the center of the compass to the desired course to determine the