SACHSENHAUSEN, Kommando KLINKERWERK, prisoner's folded letter with excerpt from the camp regulations from Oranienburg 26. 6. 42 to Silz / Warthegau, censorship single-circle stamp "Postzensurstelle G / K.L... ", the sender with the addition "Kl" for Kommando Klinkerwerk, an external camp in the nearby Grossziegelwerk with high human attrition.