In the upper right-hand corner of the cards for male prisoners, there is a number indicating the block in the main camp in which the prisoner was housed. In Buchenwald, the block numbers went up to 66. Numbers higher than 51 indicate that the prisoner was housed in what was known as the Small Camp (Kleines Lager). This was established in 1943, and the conditions there were particularly bad. On the labor assignment cards for women who had to work in the sub-camps, the block was not mentioned, so this field remained empty.