Key block for Rasterschlüssel 44, used by the German Army (RS44), and 4 manual keys for practice

Rasterschlüssel 44 scrambled the order of the letters in the plain text. A different grid was used every day. On each line, 15 randomly placed cells would be blacked out. In order to encrypt text, it was written in the grid, starting from any position, from left to right and then in columns from top to bottom.