Type D. Stores reference 14B/746. Used by photo-reconnaissance staff to view aerial photographs for interpretation purposes. The use of these helped to ascertain the accuracy of bombing, pinpointing targets and so on. The viewer is in two sections - the main body has twin lenses set within a flat metal plate with pivoting legs on either side. These fit into a base plate, with notches on the legs permitting height adjustment. Good '+' condition showing normal use and wear. Air Ministry King's crown stamps on the underside of the viewer and War Department broad arrow marked on the original faux leather case. Stock code M27508.