The weapon kept being changed. Because its first design was changed many times and the "Luftwaffe" needed different things, many different types of FG 42 were made. Papers and books written after World War II usually say that there were three main versions of FG 42. However, the Germans never said that they were different models. The "Model I", "Model II" and "Model III" were never officially mentioned. German papers just call the weapon the "FG 42". It was always the latest version of FG 42 that was mentioned.